Equity as ‘General Principles’ in the Legal Systems of ‘Civilised Nations’


Equity as ‘General Principles’ in the Legal Systems of ‘Civilised Nations’


AS OUTLINED EARLIER, the 1999 NATO intervention in Kosovo was contemporaneously accompanied by a period of reticence from many international lawyers, who were reluctant to discuss the strict legality of the operation.1 As discussed in chapter one, many of those who proffered comment upon the matter couched their analyses in terms of ‘classical international law’2 or ‘traditional international law’.3 This characterisation was accompanied to a ‘turn to ethics’ and various other attempts to advance apologist theories based on morality, politics, or near-legality. The rationale which explains this phenomenon is that it is clear from the UN Charter that any affirmation of the strict legality of NATO’s activities could be disproved by any lawyer with consummate ease.

When attempting to decide upon the legal status of humanitarian intervention, the legal provisions to which international lawyers had recourse were, naturally enough, the general prohibition on the use of force enshrined in Article 2(4) of the UN Charter and its two widely accepted derogations, the inherent right to self-defence under Article 51, and collective action under Chapter VII of the Charter. Since humanitarian intervention qua Kosovo could not fall under either of these two explicit exceptions, it was, seemingly, abundantly clear that the UN Charter prohibited humanitarian intervention.

Why therefore the notable reluctance on the part of international lawyers at the time of the Kosovo crisis to avow this easily comprehensible state of affairs? The answer, as noted in chapter one, is the unpalatable results that stem from such an avowal. In case of a Security Council veto by one of the five Permanent Members, blocking any prospect of a Resolution permitting action under Chapter VII, an adherence to the central tenets of the modern international legal regime, namely respect for State sovereignty, non-interference and the prohibition on the use of force will in fact serve to prevent action which most people would believe to be warranted and which could result in the saving of a great many lives. Being an apologist for unobstructed ethnic slaughter leaves a bitter taste in the mouth.

The particular temporal context of the Kosovo intervention may also play a part. The 1990s had witnessed gross human rights abuses, including the genocides in Rwanda and at Srebrenica. Mass media had made the world aware of the inaction or inadequate action of the UN Security Council, and the consequences which had resulted from this. International lawyers were, therefore, reluctant to adhere to a positivist interpretation of the legal framework on the use of force and, in doing so, condemn an action, which, while prima facie illegal, was perceived as having saved lives. To borrow the words of Bruno Simma, ‘could it not be that “humanitarian interventions” now undertaken in the spirit of ensuring that Srebrenica does not happen again, as it were, deserve a friendlier reaction on the part of international lawyers?’.4 The age-old Kulturkampf between morality and law was transferred to the international scene.

This battle is not a new phenomenon. It may be described as the central continuing argument of legal philosophy. Positivists such as Jeremy Bentham, John Austin and HLA Hart have long since argued for the rejection of any confusion of ‘what is’ and ‘what ought to be’.5 Conversely, natural lawyers, such as St Thomas Aquinas, Hugh Kennedy and Lon Fuller argue, in varying degrees, that a higher law or morality must regulate the lawmaker in his draughtsmanship, and those laws and legal regimes which fall too far foul of this basic morality are void – lex iniusta non es lex.6

International law is a phenomenon which is heavily criticised by several schools of international relations theory, notably Neo-Realism. Neo-Realists claim that the influence exerted upon international affairs by the United Nations, and indeed, international law in general, is a minimal one, itself a mere by-product of State power games, the ultimate goal of which is to improve one’s own position at the expense of one’s neighbour. Therefore, it has fallen to international lawyers to defend their discipline in recent decades, to reinforce its inherent value and worth, as it were, in the face of Realist assertions that States will only obey international law when it is in their selfish self-interest to do so. This affirmative role is predicated upon being able to point to written stipulations or interdictions to enforce rights and obligations upon States and other parties. Customary law may also be used as a source, but it is certainly relatively unpopular to appeal to sources outside those enunciated by Article 38(I) of the ICJ, such as the ‘law of God’ or the ‘law of reason’. This is perhaps also due to the fact that such conceptions suggest an inherent subjectivity, perhaps commonly held within each culture, and perhaps even within whole regions – a national Volksgeist as Savigny would have it – but surely no common worldwide connotation beyond the most cursory and abstract principles.

Nonetheless, despite the above trends, and despite the fact that the NATO Member States effectively did as they pleased in Kosovo, paying scant heed to their international legal obligations, either in terms of general international law or international humanitarian law, few international lawyers were wont to condemn their actions as downright illegal. The affirmative positivist trend did not extend this far. Perhaps this is a lesson from history. Gustav Radbruch fervently believed that a too-strict adherence to positivistic philosophy in pre-National Socialist Germany enabled a smoother route to dictatorship and the gross levels of abuses which followed.7 It is open to debate whether Radbuch was justified, but Allen Buchanan echoed Radbruch’s sentiments nearly 60 years later in his rejection of ‘legal absolutism’, the view that ‘it is virtually never justifiable to violate international law or at least not the most basic norms of international law, even for the sake of protecting Human Rights’.8 However, given the leaning toward affirmative positivist rhetoric amongst the international legal community in the face of the taunts of international relations scholars, it required in both historical contexts a show of armed force combined with human suffering to prick the conscience of legal scholars. Pre-war, Radbruch had been a revered German positivist. Similarly it is germane to note how in the aftermath of the NATO operations in Kosovo, pricked consciences have transformed erstwhile positivists into fervent apologists for humanitarian intervention. This was achieved by a myriad of means, including attempting to separate the legality of the operation from its ‘legitimacy’ (Kosovo Report); attempting to brand it legal simpliciter (Robin Cook and Jeremy Greenstock); exploring ‘the exception’ in international law (Martti Koskenniemi); or formulating morally acceptable ways to disobey, and in time hopefully reform, international law (Allen Buchanan). I could go on.


All of the formulae described above attempted to resolve the same problem, namely that international lawyers wished to find a solution which would broadly accommodate respect for international law, and at the same time ensure adequate – and above all effective – respect for human rights. It was a futile attempt to ‘eat one’s cake and have it too’, in my opinion, since none of the authors of these theories achieved their goal and reconciled the commands of their consciences with the letter of the law. The law just could not be stretched that far, and in moving away from law and into other domains, they opened the door for abuse of their formulae by the unscrupulous. It remains to propose an alternative formulation which might better deal with the situation. I propose to look to the law itself, and above all to its past efforts in dealing with such problems, in order to chart a way forward.

The foundation of the humanitarian intervention debate may be summarised in the following form:

The rigidity of the statutory instrument (the UN Charter, governing the use of force by States, and the ius cogens nature of the norms involved) and the factual likelihood that it will not soon be reformed (due to the interests of powerful States in preserving the status quo) result in a situation where a recognisably unjust result may occur (gross human rights violations) without the possibility of an effective solution which exists being legally achievable (this being humanitarian intervention).

It strikes me in examining this formulation that the kernel of the problem rests in the rigidity, inflexibility and stagnation of the statutory instrument at hand. The United Nations Charter was drafted at a time when human rights occupied a distinctly peripheral role in international law. This situation has known significant change in the past 60 years, to the extent that the human rights domain now constitutes one of the most important tenets of the international legal system. However, the inadaptability of the United Nations Charter, and, in particular, the impossibility of any concord amongst the Member States on reforms to the regime governing the use of force by States means that an impasse has been reached.

Legal rigidity is not a new problem. It has been dealt with in the past in various domestic legal systems. What surprises me is that the assortment of solutions proposed by the various international lawyers and politicians above discussed did not touch upon a solution which had proved effective in a variety of disparate legal regimes across the world in resolving problems wrought by legal rigidity impinging upon the achievement of just results. The solution to which I refer is equity.

In national legal systems throughout the world, equity in one form or another has served to soften the rigour of strict law. I propose to examine whether systemic trends may be traced between different national legal orders, and whether analogous equitable general principles may be observed in a broad plurality of legal systems. If such principles do indeed exist, it may be the case that they can be qualified as ‘general principles of law recognised by civilised nations’, which, per Article 38(1), constitute the third principal source of international law. If this indeed is the case, then such equitable general principles may be used in an analogous manner in the international legal arena to that in which they are used in national legal systems. If such principles are indeed identified as having normative life at international level, they could potentially play a key role as a tool to deal with legal rigidity in international law. However, before using this tool, it will be necessary to determine its existence, in the first instance via a detailed examination of equity in national law. It is to this analysis that I now turn.

A. Equity as a Panacea: The History of Equity in the Common Law

In sixteenth-century Tudor England, a long drawn-out process began to solve a problem which had beset the English judiciary system for some time. In order to undertake legal proceedings, any plaintiff was required to submit a ‘writ’. Writs were only available for certain offences (trespass, trespass to the person and battery being examples), while for other wrongs committed, no writs were procurable. Judges had attempted to create new writs, but had been prohibited from doing so by the 1258 Provisions of Oxford and subsequent orders from the monarch, who was ill-disposed towards legal reform.9 A common practice of lawyers was to attempt to ‘shoehorn’ wrongs committed into standard writs, but since the writs prescribed the elements necessary for such wrongs to be committed, such actions were usually defeated; resulting in disappointed parties who were unable to recover any compensation for wrongs suffered. This situation was compounded by the fact that the monetary damages which were generally payable as compensation were often insufficient (as the level of such damages would be determined by statute rather than by the judge himself), or completely unsuitable (when the owner would have preferred the return of a stolen object which was precious to him, for example). The legislative and executive were indisposed toward legal reform, thus the system of writs persisted. In essence:

The rigidity of the statutory instrument (the laws of England and in particular the writs system) and the factual likelihood that it will not soon be reformed (due to the interests of the Crown in preserving the status quo) result in a situation where a recognisably unjust result may occur (uncompensated damage) without the possibility of an effective solution which exists being legally achievable (specific performance of the legal obligations defaulted upon or restitution to remedy the wrong committed).

Due to dissatisfaction with the justice furnished by the common law courts of England, legal historians have cited fears in England of a reception of the Roman law to supplement, or even oust, the common law.10 Scholars at the pinnacle of the English legal profession at the time, including Starkey, debated the issue, Starkey being in favour of the reception as he did not feel the common law represented purely enough common conceptions of morality at the time – namely divine and natural law – specifically complaining that the English principles of guardianship and primogeniture were unreasonable.

The increasing importance of the need to find a solution to the inflexibility and inadequacy of the common law statutes was highlighted by the near-anarchy which resulted in the wake of the War of the Roses, due to the urgent need to restore law and order unencumbered by common law procedures and unreliable juries.11

In the end, the solution came from within the system itself. There had long existed the possibility of a special appeal to the King (or, as it was called, to the conscience of the King), via an individual petition in the wake of a result at common law that was manifestly unjust. The King would then proceed to decide on the basis of justice, whether to entertain the submission of the plaintiff, and if such submission might succeed, what remedy to award or impose. The remedy awarded by the King would not be limited by statute and could also take the form of specific restitution or performance of an obligation, and not merely the payment of monetary damages, as was the case with the regular common law courts. This system was predicated upon the medieval notion that the Prince, who is not subject to positive law, retains power to intervene to enforce a natural obligation for which the positive law is unable to provide a remedy.

Due to the instability discussed above, combined with the patent failure of the common law to meet the needs of an increasingly commercial economy, dissatisfaction with justice at common law grew amongst the population and resort to individual appeals to the monarch grew in popularity exponentially. Since such activities were encroaching too severely upon the King’s time, he delegated the responsibility for dealing with such pleas to the Lord Chancellor. In time, this also became too much work for the Lord Chancellor and his assistant the Master of the Rolls, and a separate system of courts of conscience, the Courts of Chancery, were created. They functioned separately as an alternative to common law courts for three centuries,12 until the Union of Judicature Acts 1873 and 1875, combined the two jurisdictions.13 The central tenet of the Acts was that in a situation of conflict between equity and the law, equity would prevail. Ever since, equity has functioned as a ‘softening’ influence on legal rigidity, both in England and other common law jurisdictions.

i. The Nature of Common Law Equity

It is important to realise that while equitable jurisdiction developed as a means of mitigating the harshness of the common law, one must nonetheless stress that equity’s functioning was dependent upon the framework which the common law provided. In the words of Lord Denning, ‘Equity comes in, true to form, to mitigate the rigours of strict law’.14 Furthermore, one of the hallmarks of the remedies which equity creates is that they are discretionary in nature, and will only come into operation when the justice and circumstances of the case in question demand it. As Greene MR pointed out, in common law, if such injustice leading to a claim in equity exists, ‘it must be shown to have an ancestry, founded in history and in the practice and precedents of courts administering equity jurisdiction’.15 Such a formulation, rooted in law and legal practice, was undoubtedly necessary to guard against wanton subjectivity on the part of judges when dealing with the flexible doctrines of equity. After all, it is clear that principles of certainty and consistency form an integral part of the fair administration of justice. While it is doubtless true that the precise circumstances in which equity may be permitted to intervene may well evolve as time goes by, the underlying rationale for its intervention – rectifying injustices arising from the strictures of the law – remains the same.16

The fusion that was accomplished by the 1873 and 1875 Acts between the common law and equity led to a certain level of confusion within the legal community of the day as to whether the fusion was purely of a procedural nature, or whether one might genuinely speak of a combined system. Historically, equitable remedies had been discretionary, and applied in personam, whereas common law remedies were prescribed by statute, and acted in rem. For a time, Lord Ashburner’s classic statement on the situation represented the standard position: ‘The two streams of jurisdiction, though they run in the same channel, run side by side and do not mingle their waters’.17 However, Ashburner’s position has been changed somewhat by the continuous evolution within the common law, which was expressed by Lord Diplock in the case of United Scientific Holdings Ltd v Burnley Borough Council.18 Diplock’s view was that the distinctions between common law and equitable duties had ceased to matter ‘a jot’, and were no longer of any great consequence.

However, while it is undoubtedly true that the in personam versus in rem distinction has become so blurred as to matter little anymore, it is worth remembering,19 as Hilary Delany points out, that the distinction between legal and equitable rights and remedies has not been completely washed away, since, for example ‘to obtain an equitable remedy, a litigant must rely upon the court’s discretion, whereas if he seeks a common law remedy, once he has established that a right existing at common law has been breached, a remedy will be granted’.20 However, not merely in England, but throughout the common law sphere, there have been signs in recent judgments that courts are increasingly sceptical of any suggestion of a separation of the two concepts. In England, Lord Diplock damned Asburner’s dictum as ‘both mischievous and deceptive’, stating that if the ‘fluvial metaphor is to be retained at all, the waters of the confluent streams of law and equity have surely mingled now’. In his view, since the Judicature Acts of the 1870s, ‘the two systems of substantive and adjectival law formerly administered by courts of law and courts of equity … were fused’.21 This view has found favour, inter alia, in New Zealand,22 and in Ireland, where O’Higgins CJ reaffirmed the ‘fusion of the common law and equitable rules’.23

However, while the basic purpose of equity – to compensate for the strictures of law and put right injustices – had not changed over time, its modus operandi had, even before the Judicature Acts, changed considerably. Equity had come under fire from critics who attacked the lack of legal certainty inherent in a system which dispensed justice based upon an unarticulated conception of right and wrong, known only to the judge (at this time the Chancellor), and which could obviously vary from one judge to the next. John Selden is perhaps the most celebrated of equity’s critics in this period, branding equity ‘a roguish thing … for law we have a measure … equity is according to the conscience of him that is chancellor…’Tis all one as if they should make the standard for the measure we call a foot, a chancellor’s foot’.24 Selden’s pronouncement has become a byword for the classic critique of equity and its inherent subjectivity.

With, and to some degree even before, procedural fusion, however, came the influence of the common law doctrine of stare decisis, the legal principle by which judges are obliged to obey the precedents established by prior decisions.25 Its development was instrumental in transforming equity from a mere corrective agency to a hardened system of jurisprudence. Uniform and consistent application of law provided the subjects of the common law with proper constructive notice of the permissions and prohibitions of the society in which they lived. Furthermore, stare decisis highlighted the belief that a significant proportion of law was rooted in human experience and could somehow be understood and placed within a system of substantive jurisprudence.26

ii. Maxims of Equity

As equitable jurisprudence developed, aided by the stare decisis rule, certain general principles of law began to emerge. Too broad to be steadfast legal rules, these principles were rather encapsulated by ‘maxims’, which emerged over time to establish a sort of guiding quasi-precedent on which future equitable decisions might be based. These maxims would establish the legal principles according to which equity was to be applied. However, some element of flexibility in the exercise of such principles would be retained, since, after all, equity hinged upon the justice of the case. Nonetheless, the charge of the Chancellor’s conscience being measured according to the Chancellor’s foot was duly answered. A maxim is described as ‘a conclusion of reason; a proposition to be of all men confessed and granted without proof, argument or discourse’.27

Once it is understood that the function of maxims is to furnish general principles as points of departure and not to encapsulate solutions to specific problems per se, their inherent worth reveals itself. Few have survived across all common law jurisdictions, and have adapted to a varied legal landscape over the past centuries, but those which have done so have acclimatised and survived in ‘mixed’ legal systems and have survived transplantations of law.28 This suggests their potential compatibility with other legal systems outside the common law sphere and their possible qualification as ‘general principles of law recognised by civilised nations’ within the international legal sphere.29 I shall now proceed to explain some of the most prominent equitable maxims of the common law and how they function.

a. Ubi ius, ubi remedium

An equitable maxim is ‘a summary statement of a broad theme which underlies equitable concepts and principles’.30 None are more important than the maxim ubi ius, ubi remedium, or ‘equity will not suffer a wrong to be without a remedy’. This is a truly fundamental maxim, and represents the basis of equity’s ‘gap-filling’ in particular. For example, the right of the government to inspect a corporation’s records may be clear, but its method of enforcement unstipulated. Equity will cure this defect of law.31 This is equally so when a right is conferred by statute upon an individual, but without an adequate remedy for breaches of this right.32 This characteristic is, in effect the very basis of equitable jurisdiction.33

However, the ambit of this maxim has been limited in certain ways. In the first place, it has not found favour in the criminal law as a means of setting aside rules regarding admissibility of evidence when justice demands it. Secondly, and more importantly, in order to invoke the maxim, one must demonstrate that a legal wrong – and not merely a moral wrong – exists. The word ‘wrong’ refers therefore to conduct contrary to the law rather than simply morally reprehensible behaviour. Other notable illustrations of the operation of this maxim may be found in relation to the development of equitable remedies. The concept of an injunction developed as a route to justice where the remedy of damages – traditionally available at common law – could not provide an adequate recompense. Nowadays, such injunctions, which restrain the behaviour of one of the parties, may be issued to prevent an on-going nuisance or in quia timet (as a preventive measure) to prevent a wrong from occurring.34

Injunctions are not the only example of remedies which have been devised in the spirit of this maxim. Another example has been the notion of the constructive trust, originally devised in 1972 by Lord Denning in the case of Hussey v Palmer, to be imposed ‘whenever justice and good conscience require it’.35 This resort to new remedies in the interests of justice and conscience comes dangerously close to judicial prevarication, however, and has been roundly criticised by some, including Maudsley, who said that it was possible to infer from decisions involving constructive trusts the principle that ‘in cases in which the plaintiff ought to win, but has no legal doctrine or authority to support him, a constructive trust in his favour will do the trick’.36 This has led to constructive trusts being deemed ‘a bridge too far’ for equity in some jurisdictions, such as Australia.37 Nonetheless, the very existence of remedies such as specific performance, constructive trusts, and injunctions, demonstrates equity’s flexibility in ensuring that when legal interests are unprotected, and that this lack of protection amounts to a serious injustice in the circumstances, a solution will be found.

b. Equity Follows the Law

The ambit of the maxim ubi ius, ubi remedium is tempered somewhat further by another maxim, aequitas sequitur legem – equity follows the law. This maxim is intended to place limits on the ambit of the preceding maxim, so that equity can no longer be seen as a ‘roguish thing’, as Selden one dubbed it, steeped in subjectivity. Rather, this maxim ensures that equity will not tamper with a situation when a sound, strict and indisputable rule of law already exists regarding a settled area of the law. Howard Oleck has pointed out that this maxim may be qualified as ‘minor’, since it will not generally prevent equity’s operation infra legem, or praeter legem, but merely limits equity contra legem where the rules are so clear as to leave no room for doubt.38 However, it is clear that this maxim is designed specifically to prevent widespread invocation of contra legem doctrine and to keep Pandora’s proverbial box firmly closed.

c. Equity Acts in Personam

Equity acts personally and not in rem. ‘Equity cannot presume to interfere with or to control the action of the common law courts. It acts upon the person who is inequitably suing in those courts’.39 This maxim effectively designates equity as a mandate ordering an individual party to do or not to do a specific act, upon punishment for contempt of court in the event of disobedience. This demonstrates that equity will not overrule judgments stricto sensu via the power of the government, but will constrain the parties to overrule the effects of such judgments themselves (in personam). It was said that the power of this maxim was over a man’s conscience, not his estate.40

However, the meaning and extent of this maxim have long been disputed. It has been commented that of all equitable maxims, this was perhaps ‘historically of the greatest importance, theoretically the most elusive, and practically of the most dubious significance’,41 while Delany has commented that ‘this maxim must increasingly be treated with some degree of caution’.42 Perhaps, given the confusion over how this principle operates, it is enlightening to furnish a concrete example in the form of the famous case of Penn v Lord Baltimore.43 Here, the English Chancery Courts decreed specific performance of an agreement between the proprietary governors concerning the boundaries of the American colonies of Maryland and Pennsylvania. This, despite the fact that the English courts did not have jurisdiction over land disputes in this area. The specific performance order was upon the parties, not an order for redistribution of the land itself. The idea is that the parties being within the law’s jurisdiction, even if the property was not, this maxim could be operated against their persons rather than their estates to achieve the same result. The order was not that the land be transferred per se. The order was that the party in question was to transfer the land. The order was against the party, not regarding the property.44 As time has progressed, however, this maxim has ceased to be of particular significance, but it further illustrates equity’s predisposition to going the extra mile to achieve justice.

d. Equity Looks to the Substance Rather than the Form – ex re sed non ex nomine

Equity abhors formalism and will not allow a shroud of legality to protect wrongdoers. Therefore, intended transactions that do not fulfil formal requirements will be enforced where the justice of the circumstances requires it.45 Furthermore, of tremendous importance is the fact that equity will not be constrained by the formal technical nature of a corporation or association if that vehicle is used as a shield for an improper or illicit purpose.46 The extent of this maxim is unclear, and will vary from case to case, but, as Delany notes, while this does not mean that legal formalities will not be required by equity, ‘it looks to the substance rather than the form of a transaction and does not require “unnecessary formalities” to be observed’.47 Ergo contracts may be created without observing all formalities and trusts may be created without even using the word ‘trust’; intention to create a binding instrument combined with some precatory language is sufficient.

e. Equity Regards as Done that which Ought to Have Been Done

This maxim is very much in the same vein as the preceding principle. The point of this maxim is that within a legal relationship, even if the formalities have not been observed throughout, equity will regard as done such acts as should have been accomplished had the contract been properly executed. Therefore, a specifically enforceable contract for a lease is treated as being equivalent to a lease, and all rights and duties belonging to the parties are treated as being equal to what they would have been, had the lease actually been executed. However, this maxim is again limited, as was outlined by Lindley LJ in Re Anstis: ‘The obligation to do what ought to be done is not an absolute duty, but only an obligation arising from contract … in favour of some person entitled to enforce the contract as against the person liable to perform it’.48 This case demonstrates that equity will generally not assist a volunteer in such circumstances, and that the obligation may only be carried out in favour of those persons who are entitled to specifically enforce the contract.

f. Vigilantibus et Non Dormientibus Aequitas Subvenit

Equity aids the vigilant and not those who sleep on their rights. This maxim constitutes equity’s equivalent of the Statute of Limitations and is intended to discourage unreasonable delays regarding presentation of claims and enforcement of rights.49 What is unreasonable will be determined with reference to specific circumstances.50 This principle may be divided into two separate but related categories, laches – those who neglect the upholding of their rights for so long that they may become extinguished – and acquiescence – those who fail to object or give implied assent when another party infringes their rights. However, it has been noted that such principles are only likely to apply to a relatively small number of cases within domestic legal systems, since usually such areas are adequately dealt with by statute law.51

The application of this maxim has seen divergences between the various common law jurisdictions in modern years, however. In Ireland, ‘Mere delay will not of itself disentitle a plaintiff to an injunction in aid of his legal rights’ unless statutory restrictions are breached.52 However, in a later case, Keane J held that lapse of time coupled with circumstances making it inequitable to enforce the claim was sufficient to bar the plaintiff’s action.53 In England, the position is slightly different, with Habib Bank Ltd v Habib Bank Aktiengesellschaft Zürich holding that laches is always relevant when equitable relief is sought and that no distinction ought to be made between cases where such relief is sought to give effect to legal as opposed to equitable rights.54 Delany notes that in deciding whether a defence of laches may be upheld, a court must consider in the first place whether the plaintiff has delayed unreasonably in bringing his claim to court, and in the second place whether prejudice or detriment has been suffered by the defendant as a result. Delay alone is insufficient. Such an approach means that acquiescence and laches are to an increasing extent dealt with in the same manner before the courts.55

g. Non Concedit Venire contra Factum Proprium (Estoppel)

The ‘bar’ of laches and acquiescence is paralleled by the bar of estoppel, which serves as an extension of the previous maxim.56 If a party may not sleep on his rights, then he equally may not make a representation that he intends not to uphold them, only to renege upon the assurance given at a later date. In order for one to claim estoppel, there must exist: (1) an assurance given by one party; (2) reliance thereupon by the other party; and (3) detriment resulting to the second party on foot of, and resulting from, this reliance. If this three-stage test is satisfied, then the first party will be held to be ‘estopped’ from denying his original assurance, and must fulfil whatever promise he made to the second party.57 As Lord Cranworth put it, ‘If a person makes any false representation to another, and that other acts upon that false representation, the person who has made it shall not afterwards be allowed to set up that what he said was false’.58

Although the concept of estoppel by representation is relatively simple at its core, with the three-stage test an easy barometer, in practice, it has been complicated by court judgments over time. Nineteenth-century English cases already added the element of ‘unconscionability’, that is that equity would only give relief where the truth or accuracy of a future representation had been denied in an unconscionable manner.59 Further, initially, cases were limited to dealing with interests in property, that is proprietary estoppel. However, this was extended in 1947 by Lord Denning in the famous High Trees case, giving rise to the idea of promissory estoppel, that is any promise made which is ‘intended to create legal relations and which, to the knowledge of the person making the promise, was going to be acted on by the person to whom it was made and was in fact so acted upon’, thus bringing the doctrine outside the boundaries of proprietary interests.60

The operability of estoppel outside of proprietary interests has, however, continued to be of some controversy, since the 1951 case of Coombe v Coombe declared that the doctrine might only be used ‘as a shield, not a sword’, that is as a defence, but not as grounds for a legal action.61 However, reaction to this position has diverged throughout the common law world. For instance, the position was rejected outright in Australia, with Mason CJ stating that he saw no reason why promissory estoppel might not be used as a sword as well as a shield.62 Indeed, in an earlier English case, Templeman J had adopted much the same position, rejecting the argument that promissory estoppel could not confer a cause of action, and said that it applies whenever ‘the promissor knows and intends that the promisee will irretrievably alter his position on the promise’.63 In Ireland, Costello J held that promissory estoppel could indeed give rise to a cause of action, and was also capable of creating proprietary rights.64 This has given rise to the further doctrine of legitimate expectation, whereby one may rely on promises which are believed to be made in good faith by an appropriate agent, who may not then recant his promises. Finlay CJ described legitimate expectation doctrine as ‘but an aspect of the well-recognised equitable concept of promissory estoppel’.65 It would now seem that the Coombe v Coombe position has been altered sufficiently throughout much of the common law sphere for there to be ‘but one doctrine of estoppel’.66

Another aspect of the doctrine which has provoked a certain degree of debate is the boundary limits of the three-stage test. As regards the furnishing of an assurance, with the intention that this be relied upon, it is now accepted that a conscious silence may suffice in certain circumstances.67 Concerning the element of reliance, it must be shown that the representation of the promissor ‘was calculated to influence the judgment of a reasonable man’.68 As to the element of detriment, it is for the party who has suffered the loss to demonstrate the detriment, and the causal link with his reliance upon the assurance given.69 Per Balcombe LJ in Wayling v Jones,

[o]nce it has been established that promises were made and that there has been conduct by the plaintiff of such a nature that inducement may be inferred, then the burden of proof shifts to the defendant to establish that he did not rely on the promises.70

The detriment may take any form, and need not concern an interest in land.71 However, even if detriment is established, it ‘must be approached as part of a broad inquiry as to whether repudiation of an assurance is or is not unconscionable in all the circumstances’.72

As regards the remedy available in cases of estoppel, the value of the equity in question will depend on the underlying circumstances. ‘The task of the court is to do justice. The most essential requirement is that there must be proportionality between the expectation and the detriment’.73 This was echoed in Australia by Mason CJ, who stressed that there must be proportionality between the remedy and the detriment which it is designed to avoid.74 While it might be the natural response of a court to seek to satiate the claimant’s responses if they are well-founded, if they are disproportionate or extravagant, the court will satisfy the equity in a more limited way. As Delany has noted, the question of whether the court’s task ought to be the compensation of a claimant for detriment suffered, or the fulfilment of his expectations is one which has provoked considerable academic debate, and no clear winner seems to have emerged, with – typically for equity – prudence, proportionality, and the justice of the case being determining factors.75

h. He Who Comes to Equity Must Come with Clean Hands

This maxim is highly indicative of equity’s moral origins. In order to benefit from equity, one must be free of iniquity. Therefore, any person seeking equitable relief must refrain from fraud, misrepresentation, or any other form of dishonest or disreputable comportment if this person wishes to be granted access to a remedy.76 This principle is paralleled in the civil law system by the requirement of bonne foi, for example in French contract law, which requires fair and open dealing by parties in order to qualify for fair and open treatment in court.77 In order to be entitled to the application of justice, one must have acted justly in past dealings. It is also somewhat comparable to the legal principle of reciprocity, which requires adherence to a contract on one side to allow a party to complain of his partner’s non-adherence to his obligations under the contract. However, here again, there is a caveat, as the dishonest conduct ‘must have an immediate and necessary relation to the equity sued for; it must be a depravity in a legal as well as a moral sense’.78 This restriction guards against over-extending equity’s judgmental effect to a situation where a party has been morally despicable but has no legal turpitude to answer for. It is, however, important to note that it is not necessary for the dishonest conduct of the plaintiff to have prejudiced the defendant in any way for him to be barred from action.79

i. He Who Seeks Equity Must Do Equity

The corollary of the ‘clean hands’ principle is that when one applies for equitable relief, one must equally be prepared to act in an equitable manner. One may not derive undue benefit from equity’s application, only what is due and no more. One may further be constrained, as a condition of receiving equity’s aid, to do or not to do, something which would not otherwise be necessary.80 This criterion prohibits unjust enrichment, and represents a truly fundamental maxim. In order to be entitled to the application of justice, one must be prepared to act justly in the future.81

This is one of the few maxims that can be interpreted fairly literally.82 It has also been noted that there are many illustrations of, and almost no exceptions to, this principle.83 A common example of the operation of this principle is that an interlocutory injunction will generally not be granted without an ‘undertaking’ (sum) in damages to ensure that the defendant will be compensated if the plaintiff fails at trial. This principle is also the basis for the doctrine of election, which often attaches to wills, stipulating that one may not approbate and reprobate, that is, that one cannot take a benefit while rejecting an associated burden.84 As Lord Denning pronounced, referring to this maxim, ‘if one party seeks relief, he must be ready and willing to do his part in it’.85

j. Where Equities on Both Sides are Equal, the Law Prevails

This maxim represents the intrinsic impartiality and neutrality of equity. As between equal moral rights, equitable jurisprudence is not in fact brought into play at all; the balance of moral rights being equally balanced, the legal rules may apply in isolation, without equitable considerations.86

A further minor maxim – Qui prior est tempore, potior est jure, ie aequitate – may be appended here.87 This stipulates that where equities are equal, the one which is prior in time will prevail. It is, however, a minor maxim, and not as authoritative as that which stipulates that where equities are equal, the law shall prevail.88

k. Equity Delights in Equality

This is an important maxim, also sometimes formulated as ‘equality is equity’. It operates chiefly where there are more than two parties participating in a given litigation, for example in the distribution of the assets of an insolvent debtor amongst his creditors pro rata.89 This basic doctrine applies in the absence of any clearly stated rule of law. It does not necessarily lead to precisely equal distribution of assets, but rather an equitable distribution defining ‘equality’ as is equitable given the specific circumstances of the case, as Waite J noted in the English courts: ‘This is not an area where the maxim that equality is equity falls to be applied unwittingly’.90

l. Equity Acts Specifically

The medieval common law relating to torts and contractual obligations showed a strong predisposition towards monetary damages. The idea was not to correct the wrong, but rather to compensate the wronged party. However, this was not always sufficient in the circumstances. Preferring specific performance of an obligation over the payment of damages for non-compliance as a better remedy (to put the wronged party back into the position he ought to have been in) is a central characteristic of equity’s operation.91 Since specific performance of an obligation or an injunction (eg to prevent the continuing recurrence of a nuisance) is highly preferable to damages in some instances, as it confers a worthwhile remedy to the wronged party, equity has shown its preference for this method, even contra legem in the face of statutes which have limited available remedies to fixed sums of pecuniary compensation.92

This trend may be used to describe equity’s flexibility in terms of remedies, but such flexibility is not limited to specific performance. In reality, equitable jurisprudence has demonstrated remarkable creativity in devising new remedies to do justice in the circumstances. A prime example of this is seen in the notion of an injunction. An injunction is an order restraining the party to whom it is addressed from carrying out a specific act or requiring him to perform such an act, thus imposing either positive or negative obligations depending on the circumstances.93 However, in deciding to grant such an injunction, the court shall exercise its discretion and will be wary of not unduly prejudicing the rights of third parties.94 However, it is clear that this will not always be the deciding factor, and that the defendant himself may not be held accountable for the acts of third parties.95 Although injunctions are generally awarded on the basis of a past infringement to regulate future conduct, quia timet injunctions may also be granted, before any injury or damage has been suffered, in circumstances where the plaintiff’s injury is merely apprehended or threatened. This is necessary ‘to prevent the jurisdiction of the courts being stultified’, that is to fill lacunae in the system of justice which would result if such a remedy were not available.96 However, it is for the plaintiff to show that there exists ‘a strong case of probability that such apprehended mischief will, in fact, arise’.97

The above maxim is supplemented by the minor maxim that ‘equity delights to do justice, and not by halves’. This principle affirms that equity will still give traditional remedies such as damages if this will result in a more just result.98 In short, equity looks at the best medium to place the parties back into the positions they should have occupied had there been no wrong committed, and implements this medium. This is further evidence of equity’s flexible nature, and its inventiveness with regards to new remedies.

m. Equity will not Stoop to Pick Up Pins

Equity deals only with serious injustices and does not concern itself with trifles. If the amount of injury suffered is seen to be so small as to be trivial, equity will not meddle with it. This has been described as a ‘minor maxim’,99 but its importance must not be underestimated. Equity will not concern itself with the minor injustices ‘which beset the everyday existence of every righteous man’.100 Rather it confines its ambit to remedying the grosser injustices, which have the potential to seriously affect people. This allows equity to claim a certain gravitas, in that it only enters the fray when important matters are at stake.101

n. Equity will not Decree a Vain Thing

Equity deals with making a practical and real contribution to substantive justice, not with making legal decrees or judgments which cannot or will not be carried out.102 Equity, in short, is designed to help people attain justice. If it cannot, it will not get involved.

o. ‘Equity’s Darling’

To temper the application of the list of the maxims above, equity in the common law system has also produced one last innovation which merits a brief description, this being the category known as ‘equity’s darling’.

Over time, a rule developed whereby a bona fide purchaser for a fair valuation of a property, without notice of a legal estate or equitable interest being held in the land which he was buying belonging to another, would take the land free of any equitable interest of which he had no notice. This device again demonstrates equity’s concern with being fair, assuming that if someone was genuine, honest, and paid the full price, having made adequate inquiries about the property he was buying, he would not later be penalised by any ‘surprises’ which might be sprung upon him by parties unknown after the transaction had been completed. This purchaser was nicknamed ‘equity’s darling’, since equity would not be applied to deprive him of his interests.

However, the above position was tempered somewhat by the doctrine of notice. If the purchaser had notice of the interest, then such a position would not apply. This was equally the case if he failed to make all enquiries and inspections which he ought reasonably to have made, judged with reference to standard conveyancing procedures. In this instance, even if he was not actually aware of the interest, it would be deemed that he should have been aware, via the doctrine of constructive notice. Also, any information which an agent of the purchaser is aware of, or should have been aware of via the doctrine of constructive notice, will be imputed to the purchaser himself via the doctrine of imputed notice.103 This again demonstrates that equity will aid those who are of good faith from suffering wrongs, provided that their own negligence is not a contributory factor in such wrong being suffered.

B. Common Law Equity and Legal Rigidity

The value of the historical precedent of equity in the common law cannot be overstated. Here we have an example of a system of general principles, developed organically and over time by the courts, which dealt successfully with not one but a series of manifest injustices which arose in the common law legal system. Furthermore, this system was not merely adopted in England alone, but throughout the various common law jurisdictions of the world, including well-developed legal systems such as those of Ireland, Australia and New Zealand. Moreover, these general principles developed from a system which at first was dubbed too loose to administer objective justice to something else entirely – a system of principles, which while flexible, were nonetheless sufficiently concrete to not be used over-extensively, and to result in a justice which became increasingly predictable and uniform. In reality, in England, as elsewhere, while the import of general principles and maxims of equity has remained, their explicit invocation has waned. This is largely due to the increasing complexity of the law and the fact that multiple series of court precedents invoking equity to temper the law’s letter improved legislative finesse. Lawmakers wished to see the letter of their laws respected, and to do so required coherence with equitable principles, ergo laws were drafted with such principles in mind. However, when clashes occur, as they still do, equitable principles are still imbued with the same normative force.

Clearly, such principles are adept at solving a myriad of individual problems stemming from legal rigidity. However, from the point of view of the humanitarian intervention debate, we must not take too much from this precedent. While the common law tradition represents one of the world’s most widely-used and respected legal systems, the judgments of the World Court have already demonstrated that, approval by one major legal system does not merit a principle’s adoption as one of the ‘general principles of law recognised by civilised nations’.104 Therefore, wholesale transposition of the maxims of equity would be a bridge too far. However, the cases discussed in the preceding chapter show that, while the test for what constitutes a general principle in the eyes of the World Court is not entirely clear, evidence that principles are ‘generally accepted’ amongst major legal systems may be important in determining whether they qualify as a component part of the third source of international law.105 Bearing this in mind, it seems appropriate to dedicate the remainder of this chapter to an examination of whether such principles of equity à l’anglaise – or something approximately equivalent to them – exist in other systems of law. If, indeed, other legal systems have crafted an equivalent set of principles to deal with legal rigidity and injustices in specific cases, it may well be that such generally accepted principles constitute ‘general principles of law recognised by civilised nations’. If this indeed transpires to be the case, then the third source of international law may yet shed unexpected light on the humanitarian intervention conundrum.


In order to undertake an examination of equity outside of the common law, it is insufficient merely to take the maxims and remedies devised by equity within the common law system and examine whether these same devices exist elsewhere. The system of equity which developed in England and spread throughout the common law world developed organically according to the legal landscape and historical period with which it was faced. All things being equal, things may have developed in the same manner outside of the common law realm. All things, however, are, and never were, equal. The principles which grew up in the English law cannot expect to find carbon copies in other legal systems. As Francioni notes, ‘Equity is a polymorphous concept even in the narrow confines of legal language’,106 though the same author does go on to posit the existence of ‘a common sense of fairness and equity among the different peoples of the world’.107 Our search, then, rather than seeking identical principles to those furnished by the English case, will be for principles that are broadly equivalent, which tackle legal rigidity, which display the hallmarks of equity, and which are used to render justice in circumstances when the written law is insufficiently equipped to do so.

The purpose of the remainder of this chapter, then, shall be to examine the origins of equity, and to look at how it has developed, and how it has been translated into general principles in legal systems outside of the common law. While a completely exhaustive study of every legal system worldwide would be excessively demanding for a study of this size, I shall nonetheless furnish a cross-section of a wide variety of major legal systems, many of which have known transplantation to other States. For this chapter section, I am deeply indebted to – and shall draw heavily upon – Ralph A Newman’s 1973 work Equity in the World’s Legal Systems.108 This book, edited by Newman, consists of a compendium of essays comparing the import of equity in a variety of legal systems. It has served as a starting point for research on a number of systems with which I was largely unfamiliar, and much of the wisdom contained in this volume has been reproduced in the following pages, accompanied by a large number of other sources. Sources on comparative equity are so rare as to be almost a non-category. Without this collection of essays, therefore, structuring the following section would have been overly burdensome, and perhaps near-impossible to complete in an adequate manner. I feel it is therefore appropriate to acknowledge my debt to its various authors in this regard.

However, the forthcoming section seeks not merely to reproduce the research of others, but to build upon it. In comparing the various legal regimes in the selected countries, it is my hope to discover common trends, which may help to identify ‘general principles of law recognised by civilised nations’. International normative consequences may be divined from an in-depth comparative analysis. If a legal principle is prevalent throughout the systems examined, there may be sufficient cause for supposing that it has known transposition to international law. Subsequent chapters will deal with whether any such principles have been used by the World Court as further evidence of their existence as international legal norms.

A. The History of Equity outside the English Common Law

In recounting a history of the conception and development of equity as a legal concept outside the common law, one is forced to paint with a fairly broad brush. In reality, equity has been a notoriously difficult term even to define, with different descriptions in each legal culture, and with one commentator noting that ‘The only common element is a term whose connotations are famous for their generality, vagueness and ambiguity’.109 Rossi comments that its history ‘has not produced an accepted definition of its constitutive elements, its function, or its application. In both theory and practice, equity is shrouded in mystery’.110 However, perhaps it is as well to heed the advice of Richard Falk, who counselled that equity is better discussed than defined.111

The history of equity is a disputable one, according to Rossi, revealing two disparate interpretations. A first school indeed considers equity in terms of a corrective utilised principally by judges to mitigate unnecessary hardship caused by the application of general principles or specific rules, but this interpretation is disputed by a second school which considers equity within the framework of the natural law, and imparts to it the character of a source of law, while viewing equity as an inseparable component of the process of adjudication. In reality, it is probably somewhere between the two. Certainly the ancestry of the concept cannot distil to a single legal system, with the concept of equity being expressed, inter alia, in the legal systems of Ancient Greece (epieikeia – clemency); Ancient Rome (aequitas – equality); traditional Chinese law (Ch’ing – compassion); and the Hindu tradition (Dharma – righteousness).112 However, the links with natural law must be addressed before proceeding further, for fear of confusing the two concepts.

i. Natural Law and Equity

The links between the classical conception of equity and that of the natural law spring largely from the notion of conscience. While natural law is traditionally portrayed as a compelling force decreed by a higher power or higher morality which may override incompatible man-made laws, the truth is that many of the best-known examples of natural law being invoked have sprung from the demands of the consciences of those who sought to invoke it. I am not the first to note this. R Neil Snyder points out that Antigone’s famous resolution of her dilemma ‘is a dramatic example of the capacity of men [or in this case, women] to rise to the impelling demands of conscience, recognise an unjust element in the hierarchy of normative commands, and refuse such elements’.113 Snyder also notes that Martin Luther’s famous declaration that ‘Ich kann nicht anders tun’ (is the assertion of conscience in consonance with a ‘higher law’).114 These examples show that, while natural law was conceived of as a higher law being invoked by reference to a higher authority – namely God – it was a fundamental objection of the complainant’s conscience that called him or her to refer to such law. Parallels may be drawn with equity, qua common law at least, where a fundamental injustice in the domestic legal system cause the plaintiff to appeal to the conscience of a higher authority – namely the King. While natural law was not limited in its extent by the conscience of any person in particular, resort to its content would be preempted by the demands of one’s conscience. In order for such a demand to be well received, it would, at the very least, be necessary for any such ‘commands of conscience’ to be in accordance with common conceptions of moral conduct at the time. Likewise, as equity evolved, its association with the power of the King faded, and it became associated with the notion of ‘unconscionability’ – that is, a result arising from the law which would so offend the moral conscience of a reasonable man at that time and place that resort to equity would be called for.

If one understands equity and natural law in the manner described above, it may seem that there is little enough to distinguish them. Indeed, Rossi has described Aristotle’s conception of equity as ‘an extension of natural justice [ie natural law]’.115 However, while this may be the case, Aristotle’s conception of equity spoke of equity as a concept somewhat at odds with that of the natural law, not as a hierarchical legal source, a sort of natural peremptory normative bloc, but rather as a corrective mechanism. He argued that in any situation in which the law may speak universally, but in which the issue at hand happens to fall outside the universal formula, ‘it is correct to rectify the shortcoming, in other words the omission and mistake of a lawgiver due to the generality of his statement’.116 Per Aristotle, such a rectification in fact corresponds to how the lawgiver himself would have legislated, had he foreseen the possibility of such a situation arising. ‘That [therefore] is why the equitable [solution] is both just and also better than the law in one sense’.117 Rather than being an extension of natural law theory, in expounding equity as a corrective, Aristotle instead ‘provided the theory which integrated equity into the spheres of legal justice [ie law stricto sensu]’.118 As Snyder notes, a legal system which is predicated purely upon positive law alone tends to substitute order for order’s sake in the place of order as a means of achieving justice. This construction tends to forbid judicial innovation when judicial innovation may be warranted and even essential in a given context. Furthermore, it may result in the upholding of rules and regulations where to do so is both unjust and impracticable.119 Without resorting to the disputed normative category of natural law, equity as a corrective mechanism, as described by Aristotle, enables the general rule to be modified with reference to specific (and presumably unusual) circumstances which could not have been foreseen by the legislator at the outset.

Of course, while the employment of equity as a corrective mechanism sounds attractive on the face of it, particularly as an alternative to the notion of a hierarchically superior ‘natural law’ which may make rubbish of our own norms at a stroke, the fact is that it will always be difficult to define what the ‘demands of one’s conscience’ or the ‘demands of the conscience of a reasonable man’ actually constitute. Roscoe Pound brands equity ‘a universal element in that it aims to indicate a standard in the maintenance of which the administration of law corresponds to a man’s best social nature’.120 Per Pound, such universal elements are within social control, insofar as society (ie people) has been able ‘to discover by experience and test by reason. In essence, these are what Duguit describes as the principles of social solidarity; those principles which maximise co-operative tendencies and forestall social disintegration’.121 As such, the corrective may in turn lead to law reform, either by means of the use of equitable precedents, or by actual legislative correction, to fill the lacunae which equity seeks to address. Thus equity may serve ‘as the bridge between the world of strict law, precedent and custom, to the realisation of the perfectibility of legal rules’.122 This formulation is certainly attractive, although the problems as to equity’s somewhat indeterminate content remain.

A further problem, and one that can certainly be keenly felt as regards international law, is the distinction between the usefulness of equity as a palliative to inherently unjust solutions, and the damage that a somewhat indeterminate corrective may do to the established order within any legal system. This is certainly also a point which equity shares with the natural law, and it is a concern that shall be further discussed in later chapters. For the present, it is sufficient to note the fact that as regards equity, this is not a new concern. As early as 1765, Blackstone, in his renowned Commentaries, stated that, for the sake of the order of the legal system, the freedom to consider cases in an equitable light should not be pushed too far, ‘lest thereby we destroy all law’.123 The test that Blackstone proposed was whether a specific application of an equitable principle would lead to an essential realisation of justice in the circumstances, while conforming to a moderate sense of ‘fairness’, or whether in securing the plaintiff’s wants, it would be done so at the cost of others. Snyder broadens this concept, arguing that an act-utilitarian analysis of equity must be balanced by the rule-utilitarian consequences which would ensue were any such corrective device to obtain a permanent position within the legal corpus. Thus,

occasionally, the immanent cry for ‘justice’ in a particular case must be unanswered because of broader social reasons; an occasional individual injustice being part of the price of the broader justice enjoyed by all if social order is to be preserved.124

ii. Equity and Roman Law

Having thus distinguished the métier of equity from that of natural law, we are free to proceed with our exploration of equitable principles outside the common law sphere. The obvious point of departure for this purpose would seem to be in the Roman law, it being the antecedent of many of the modern legal systems of the world. It is particularly true that the bulk of those legal systems which have not known the influence of the common law of England have received, to some degree or another, key elements of the Roman law and have incorporated them as cornerstones of their legal systems. Exploring the impact of equitable principles within the Roman law, then, is necessarily of singular importance if we are to admit that they form part of the ‘general principles of law recognised by civilised nations’.

Sir Henry Maine has noted that equity gained currency at an early stage of the development of the Roman law system, as indeed had been the case in the common law. He defined equity as ‘a set of legal principles, entitled by their intrinsic superiority to supersede the older law’.125 This reference to ‘intrinsic superiority’ may be contrasted with the concept of normative superiority. To Maine, then, it was not the normative source of equity, but rather the nature of equity’s intrinsic content, which allowed it in certain circumstances to supersede the positive statute law. However, whether this represented the legal position in Roman times is less clear.

Early Roman law was characterised, much like common law prior to the advent of equity, by legal rigidity. The Twelve Tables were enacted in the mid-fifth century BC, and contained the principles of the ius civile – the civil law. Those principles which came to supersede such law were regarded as ius gentium – that is, principles ‘common to all civilised people, because they appeared to be dictated by the common sense shared by all such people’.126 This represented a sort of rights-based corpus, which was unfettered by the notion of citizenship, and applied equally to all people, regardless of whether they were Roman citizens or not, which was not the case with the ius civile. Justinian’s Corpus Iuris Civilis of 529–34 AD offers an excellent understanding of the development of Roman law over a period of almost 1,000 years dating from the adoption of the Twelve Tables, and charting the interaction between the ius gentium and the ius civile.127 The Corpus Iuris Civilis (also known as Justinian’s Digest) and subsequent commentaries make clear that, over time, the ius civile became increasingly refined, and began to afford particular protection of rights to the Roman publicus. Rossi notes that through this process of refinement at municipal level, the equitable element in the ius civile began to expand from a vague notion of the comportment of a good citizen – roughly equivalent to the ‘reasonable man’ qua common law – to a set of small, albeit inconsistently applied, procedural remedies, largely affecting the areas of proprietary rights and contract law.128 However, Rossi notes that such rights were only applicable to Roman citizens, and such equitable expansion did not take place in dealings with foreigners.129

Nonetheless, the ius gentium was also experiencing a process of change, although this began somewhat later than the ius civile. As the parallel universal system matured, it began to incorporate what had become fundamental principles of Roman civil law into its own free-standing legal structure. Of these principles, good faith (bona fides) was the most important as it served as the bedrock of many key tenets of the Roman legal structure. It is noteworthy by way of example to cite the fact that virtually all actions arising from consensual or real (proprietary) contracts (pacta sunt servanda), rei uxoriae, quasi-contract and the protection of the interests of third parties (negotiorum gestorum) and fiduciary guardianship (tutela fiduciaria) were guided by this principle of good faith.130

However, despite the development of rights within both the ius civile and ius gentium, the legal system had remained relatively rigid as regards both remedies and statute law. This resulted in not infrequent denials of justice, even in cases where recognised rights had been infringed. It therefore fell to the praetor urbanus – the chief city magistrate – to issue remedies, which were termed ius honorarium. Such remedies were proclaimed by way of praetorian edicts (an approximation of something between civil regulations and public judgments), which built up into a corpus of binding precedents. While technically the praetor was forbidden from making use of such powers to legislate (and could be tried for treason if he did so), in reality, the fact that such precedents were binding gave them the force of law and regulated the conduct of citizens. In this respect, the praetor’s powers were both legislative and judicial, and he possessed power to issue edicts (ius edicendi) to aid, supplement, or correct the existing law, that is infra, praeter, or contra legem.131 Through the use of such edicts, successive praetors created alongside the narrow, formalistic civil law a body of flexible, adaptable law more sensitive to the demands of justice. This ius honorarium gave ‘better’ remedies to right-holders, and even created new rights where none had previously existed in the interests of justice.132

Commentaries on the praetors’ activities show that practices developed over time to keep the impact of the subjectivity of the personal judgment of any one praetor to a minimum, much as common law equity responded to John Selden’s taunt regarding the Chancellor’s foot. It became clear that if the praetor used his power too enthusiastically, he would undermine public confidence in the law and its forms. Nonetheless, principles of remarkable similarity to those teased out by equity’s practice in the common law may be observed in the ius honorarium. For example, the praetor was concerned to apply the principle that parties who had seriously and earnestly entered into a transaction with honest intentions of completing a bargain ought to have such intentions fulfilled, even in cases where they had failed to adhere to the particular formalities laid down by the law. Such tendencies were exemplified by the development of the idea of ‘bonitary ownership’ (roughly equivalent to an equitable interest) in Roman law, and parallel the development of the common law principle that ‘equity looks to the substance rather than the form’.133

Further, the ius honorarium could correct the civil law by conferring a remedy upon one person, where someone else may have been equally or more entitled at civil law, because the praetor considered the grantee more worthy of protection, often due to having behaved himself equitably and in good faith throughout. This parallels the common law doctrine that equity will not prejudice the interests of a bona fide purchaser for value without notice of any wrongdoing. It was also notable that the praetor was often prepared to go outside the boundaries of the statue law in conferring remedies upon individuals. For example, where only damages were provided for, but where restitutio in integrum would provide a more adequate compensation, this is what the praetor would ordain.134 This was in strict contrast to the traditional ius civile, which, akin to the statutory common law, ‘aimed not at making a party carry out his contract, but at making him pay for not doing so’.135

The principle prohibiting unjust enrichment was set out clearly by the praetors, and was incorporated into Justinian’s Digest.136 Furthermore, another principle consecrated by the ius honorarium stated that no one may take advantage of his own wrong. This was in contrast to the position regarding fundamental error, which vitiated the transaction ab initio, whether it was bona fides or stricti iuris.137

A further point of note is the palpable protection that the ius honorarium afforded to those parties who found themselves disadvantaged for whatever reason. Stein devotes considerable attention to this area, noting that praetors were not wont to apply legal rules to the prejudice of those who, for any reason for which they are not themselves to blame, are incapable of amply safeguarding their own interests. For example, where a man had been disenfranchised of some rights, particularly property rights, through lapse of time (prescription) or through non-appearance in court to contest his rights, because he was absent on State affairs or had been captured as a prisoner of war, he could later obtain restitutio in integrum and be restored to the position he would have occupied, had the prejudicial event never occurred.138

Another example of the above is the position concerning persons who have reached their majority – that is who are adults and who have attained full legal capacity – but who are at a distinct disadvantage by reason of their circumstances. For example, in Roman times, it was the custom that at the age of 14, a young man would quit his tutor, and was therefore considered to all intents and purposes to have become an adult. However, it is clear that a young man of 14 is hardly capable of looking after his own interests when he partakes in commercial transactions, and already in the third century BC, a statute entitled the Lex Laetoria provided him with a defence if he was sued by one who had deliberately taken advantage of his greenness. Later, the praetor was to grant him restitutio in integrum of a transaction where he had suffered loss, harm or damage through his own inexperience or through the fraudulent machinations of the other party. The result of these successive measures was that persons would not transact with young adults between 14 and 25 years of age, unless they were accompanied by an independent adult to advise them, and the appointment of such a person, known as a curator, became standard practice.139 This final example is of particular note, as it mirrors the position which the modern common law has adopted in most jurisdictions relative to those persons who are at risk of making a bad bargain by reason of exploitation by another who may be in a stronger position. Such has developed into the doctrine of undue influence, and while the age of legal majority is higher now – 18 in most jurisdictions – there remain categories of persons for which the modern law retains a special level of concern. A prominent example is when a wife makes a transaction with a bank which may not be in her best interest, the bank is obliged, when negotiating with the wife, to take note of the fact that her husband may exercise influence over her, and that the transaction may therefore either be entered into either with faulty information on the part of the wife, or to some extent à contre-coeur. Such is the regularity with which such manipulation of wives by their husbands in transactions of this kind occurs that the bank is obliged to ensure that the wife has taken independent legal and financial advice, either from a solicitor, a financial advisor, or another informed and independent person before the transaction is carried out. If this is not accomplished, the bank risks the annulment of the transaction ab initio for undue influence, of which it was constructively notified by the circumstances of the transaction.140

Overall, then, the Roman ius honorarium displays many of the tenets associated with equity qua common law. A preoccupation with standards of reasonableness and good faith is evident throughout, as is the careful balance between occasionally setting aside the rigid letter of the law in the name of justice and an awareness of the damage it could do if the legislator’s powers were seen to be usurped by the judiciary. Over the course of the period catalogued by Justinian’s Digest, aside from the edicts of the praetors, there are many further examples of imperial interference with the application of the classical rules of Roman law ‘in the course of efforts to protect the weak against the strong’.141 Judges were also instructed to apply the law ‘benevolently’ or ‘equitably’. Equity’s stamp on the Roman legal system, then, is unmistakable.

iii. Equity in Muslim Law

The idea of a religion – and more particularly religious dogma – influencing a legal system is not an alien one to Western scholars. On the contrary, the influence of canon law upon Western legal systems has been significant. However, while others have endeavoured to chart the influence of equitable principles and equitable doctrine on canon law,142 I consider it beyond the ambit of the current study to do so. The reason for this is that we are presently attempting to undertake a study of the impact of equity as an element of ‘the general principles of law recognised by civilised nations’, a particularly distinct category. The profound influence which equity in the Roman law and common law models have had upon modern legal systems merits their inclusion and examination in such a study. However, the influence of equity in canon law has been restricted by the Church, and since such a position does not seem to reflect any of the modern predominantly Christian States around the world – save perhaps the Holy See – a detailed analysis of equity’s place in canon law seems superfluous here. It will suffice to say that despite the initial reluctance of the Church to concede a role to equity, such a berth was eventually created for a limited number of principles, and canon law is not therefore devoid of equitable considerations. Van Hove notes that written and unwritten sources of equity may be employed in such circumstances,143 while Lefebve recalls the judicial rule of Pope Leo XIII that ‘in extreme cases, equity shall prevail’.144

The same peripheral role accorded to canon law may not be accorded to Muslim law, however. The permeation of religion into political and legal systems throughout the Islamic world is such that religious principles dominate many national legal systems.145 While certain predominantly Muslim countries have modernised their legal systems, and have adopted a secularist model based upon Western values,146 the majority of such States have remained true to the commands of their religion in many aspects of their legal systems. Such positions have been eroded in recent years by the human rights movement to some extent, but the civil law position remains broadly constant.

The Koran, the Sunnat, the Idjmaa and the following of the rites – these being analogy (Ghyas) and reason (Aghl) – are the four principal sources of Islamic law, while usage, custom and doctrine play a less important role.147 According to Islamic ideals, God is the one ‘true’ legislator. Justice in Islamic law is described as a search for the truth rather than a balancing of competing legal interests. The Sourat stipulates that the Islamic faith, and therefore Islamic law, has been perfected, and legislators must therefore not diverge from it.148 As Afchar has noted, ‘the role of Equity in a juridical system in which the legislator no longer makes laws is and must be enormous’.149 This would seem to be reflected by legal–religious texts, particularly the Sourat, which states that equity must rule in Muslim society, and encouraging followers not to follow passion to the detriment of equity.150 There are further references to the Prophet ordaining that equity must rule amongst the faithful,151 and that God himself has ordered equity.152

However, the precise content of Islamic equity remains to be examined. There are two words which find common usage in Muslim law, both of which can be considered to be a translation of the concept of equity. These are Adle and Insaf. Afchar notes that certain Islamic schools, amongst them Matazala and the Chiites, consider equity to be one of the Divine attributes, for iniquity – and by extension a complete absence of equity whereby unjust results cannot be corrected – is irreconcilable with the power and infinite wisdom of the God of the Koran, the lawgiver of Islam.153

As to how these equitable principles are realised in practice, the great rule that no one may cause unjust harm to another (Lazaar) underlies all dealings in Islamic law and which may never be surpassed. Two principal sub-rules may be derived from this, namely that God will require of no man more than he himself can accomplish.154 This may be translated as the beginnings of a standard of reasonableness in conduct, which is certainly a common equitable principle in various legal systems. The second sub-rule is that bad faith will never receive protection by legal means. This stipulation finds a parallel in the Western conception of bona fides and the theory of the prevention of the abuse of one’s rights. Further, Afchar notes that 18 separate verses of the Koran affirm that each man shall be rewarded only according to what he has accomplished (and not further).155 This is clearly an approximation of the common and civil law doctrine of the prohibition of unjust enrichment.

Far from being a legal system in which equity is an alien element as one might have imagined at the outset, Islamic law, being strongly underpinned by ethics, has long been a system which protected the rights of those who were wronged but for whom the law was ill-adapted, this being the very role that equity was intended to play. What is perhaps interesting is that it was not merely Islamic judges who were expected to employ equitable formulations in their decisions, but rather every individual was formally required by law to act in an equitable manner toward his neighbour. What this entailed in concreto was more than merely refraining from encroaching upon others’ rights, but rather for each person to be somewhat indulgent toward his neighbour and not exercise his rights in violation of his neighbour’s interests unless it was completely necessary. This could extend to suspending journeys to help sick travellers (which may be paralleled with the French ‘duty to rescue’), a duty to help hungry neighbours and a variety of other such rules.156 The role of ethics seems to be significantly stronger in Islamic law than either the Romano-Germanic of common law systems. It is worth recalling, for example, that the common law duty of care model, based upon Lord Atkin’s famous ‘neighbour principle’, which gave birth to the entire law of tort (non-contractual) negligence liability only came into being after the celebrated case of Donoghue v Stevenson in 1932.157 It would seem clear that a similar extensive duty of care towards those with whom one had contact but no actual contractual links, existed in Islamic law many centuries before this date.

Afchar notes that in contractual relations, while equitable conduct is required throughout dealings for the party’s conduct to be valid, equity itself is reducible to a series of maxims. These include: that one must not overreach one’s co-contractor by way of lesion; that one must suffer the loss resulting from the contract if one’s co-contractor is economically weak; that one must not be obdurate in demanding performance; that one must pay readily one’s debts without waiting for money to be demanded or legal action to be taken to extort it; that one must agree readily to prior rescission of the contract if the other party requests it; and that if one makes a contract with a person who is in an economically weak or otherwise disadvantageous position, one must do so having taken all relevant precautions, and with the knowledge that one may be required to relieve the other party of their obligations if they are unable to carry them out by reason of their disadvantage, economic or otherwise.158

This inexhaustive list of maxims does not precisely parallel that of the common law, or indeed the model furnished forth by the Roman law, though it would be foolish to say that they do not have a great deal in common. In the end, it seems, that, as elsewhere, equity in Islamic law is a device which is renowned above all for its flexibility and which may adapt to given situations as they come before it. If injustice or an unsatisfactory result is forthcoming due to inherent inadequacies of the statute law, ‘the walls of the statutory rules, sooner or later, yield before the assaults of this eternally vital element’.159

iv. Equity in French Law