The study of the laws governing the functioning of the United Nations Security Council (SC) has fascinated generations of scholars from various fields, including international relations, history and law. From international legal perspective, the main point of attraction is represented by the powers bestowed on the SC by the founders of the UN Charter. Such powers are both legal, as long as they have been enshrined in the UN Charter, and highly discretional, since they are not subject to the formal scrutiny and control of any international subject other than the SC itself.

The history of the United Nations shows that the SC has acquired a special status in the international plane as one of the principal bodies of a quasi-universal international organization and, at the same time, as a global actor on its own. This has generated a growing concern among the international community about the legitimacy of SC actions. Hence, demands for reforming the SC started to be raised in 1955, when the process of decolonization led to a significant increase in the UN membership.¹ Since then, proposals for reform have focused on three main domains—namely, the issue of composition of the SC, the issue of veto power and the issue of transparency of its decision-making process.

As of today, the issue of reform of the SC remains one of the great constitutional challenges of UN law. Indeed, although proposals for reform presented over the years have been mainly motivated by political reasons, they have inspired a wealth of scholarly contributions on this topic.² The academic debate proves to be particularly variegated as different contributions draw upon different conceptions of both the role of the United Nations in global politics and the role of the SC as a global actor. For instance, the United Nations has been referred to either as a tool of Great Powers, a vision according to which the UN is a creature of the world’s strongest states, or as governor of society of states, a conception of the United Nations as the guardian of an agreed-upon set of norms and values, namely the one embedded in its constitutive Charter.³ The majority of contributions on the role of the SC, on the other hand, characterize it as the world government and point out the risk of it growing into a Leviathan.⁴ The main signals of this potential—or, for some, actual—authoritarian drift pertain to the current SC composition and decision-making procedures, including the existence of veto powers.

A common trait of all academic contributions is that they recognise that in order to be effective in the international plane, the United Nations has been created with a necessary element of power to be shared by member states through the work of its main organs.⁵ The division of power, however, has been unequal among member states and primary bodies alike, as the provisions of the UN Charter establishing the SC demonstrate. Acknowledging this fact, international scholars have often characterized the legal status of the SC as problematic and have called for SC reform.

From this perspective, the debate about reforming the SC can also be qualified as a discourse about taming global power. It therefore represents an issue of global constitutionalism, since the latter concerns itself profoundly with allocation of power and institutional efficacy.⁶ In part, the history of the debate about SC reform reflects this standing so long as states have never really questioned the existence of permanent members, but rather who should be regarded as a Great Power.⁷ Accordingly, some argue that the composition of the SC should reflect the democratic representation of the wider UN membership, while others maintain that the composition of the SC should represent global powers.⁸ However, both in theory and in practice, it is difficult to determine which position better serves the purposes and principles of the UN Charter and whether it is necessary to have a democratic SC in order to maintain international peace and security.⁹

Scholarly literature on the mandate and the powers of the SC has examined various aspects of the functions of the SC stemming from Article 24 of the UN Charter and how they relate to general international law.¹⁰ Certain scholars also argue that the SC has gradually developed its legislative competencies beyond the text of the UN Charter and probably in violation of international law.¹¹ Consequently, other scholars have proposed different approaches to what they perceive as a necessary curtailment of SC enforcement powers.¹²

The contribution of such a body of literature to the rationalization of principles of law governing the functioning of the Council is highly relevant. However, SC practice has never been analysed in a systematic way, with the consequence that, as of today, we do not have a comprehensive picture of the extent to which, if any, the often advocated rules of international law are able to constrain the discretionary powers of the SC.

Existent scholarship provides an account of the legitimacy of SC actions (and inactions) from a theoretical perspective using selected resolutions as case-studies.¹³ Such a vast body of literature has covered various fields, ranging from the limits of the SC mandate to its lawmaking powers,¹⁴ and has devised a number of conceptual templates whose relevance within and outside the academia cannot be underestimated. However, due to the nature of the inquiry, traditional analysis turns out to be rooted on assumptions or generalizations derived from the study of selected, though important, SC resolutions. Consequently, its findings are supported by little evidence of consolidated SC practice.

For example, it has become commonplace to argue that the decision-making at the SC is ultimately governed by reasons of political convenience.¹⁵ The main argument put forward to support this view is that the presence of five permanent members (P5) endowed with veto power over resolutions determines that the SC mandate can be executed only when there is agreement among them.¹⁶ As a result, situations representing actual or potential breaches of international peace and security are likely to be overlooked whenever they involve a direct interest of a P5.¹⁷ This seems to be confirmed by the fact that, for instance, since 1946 not a single resolution has been adopted on Tibet or Chechnya while only one has been adopted in 1960 on the relationship between Cuba and the United States.¹⁸ More recently, a draft resolution on Crimea has been vetoed by one P5, due to opposed views and conflicting interests with the proponent P5.¹⁹ However, as of today no study has ever provided a detailed list of the issues addressed in the resolutions adopted, with a view to ascertain the overall degree of legitimacy and effectiveness of such actions.

The present study aims at addressing this knowledge gap. The purpose of the research is to establish the extent to which, if any, international law is able to limit the discretionary powers of the SC, and how the behavioural patterns of the SC contribute to the creation or development of international law. In particular, this study aims to determine how international law influences the politics of the SC and how the politics of the SC contribute to the development of international law.

One of the reasons for the existent gap in the literature can be ascribed to the limits of the traditional, doctrinal method of inquiry, which is grounded on theoretical assumptions against which selected case-studies are assessed. Thus, to pursue a systematic and comprehensive analysis of SC practice from the origins up to the present, I have adopted an empirical methodology—namely, the one that falls within the tradition of Empirical Legal Studies (ELS).²⁰ This is an innovative approach in international law because by using quantitative techniques, it provides new insights on how UN law actually works in practice.²¹ The analysis, however, is meant to complement doctrinal scholarship on SC powers without replacing it.

Quantitative analysis depends on the language of numbers, which makes the empirical evidence particularly hard to contradict or deny.²² Thus, the bulk of the analysis is based on simple statistics describing patterns of SC resolutions. The caution though is that ELS cannot be regarded as an end in itself, because counting for the sake of counting amounts to nothing. This means that any empirical study on law, including the present one, presupposes a background of doctrinal and normative analysis.

As an autonomous field of research, ELS possesses its own distinctive features. Generally speaking, two elements characterize the empirical research in social science. The first one is represented by the systematic nature of the process of collecting and analysing the information.²³ The second one consists of the rather descriptive way of presenting the results of empirical legal research, which is followed by a discussion of the implications of the empirical evidence. A corollary of the second rule is that, unlike other empirically oriented fields such as socio-legal studies and law and economics, ELS is limited to the analysis of a strictly legal issue and does not address other extra-legal concerns.²⁴

To collect the information needed to conduct the empirical study of SC practice, an original database has been created. Using the descriptive formulation provided for each resolution in the SC digital archive,²⁵ the entire body of resolutions has been reorganized into categories—namely, resolutions on geopolitical regions, thematic resolutions and a residual category—and sub-categories. The process of coding data allows to reconstruct groups of re-cited resolutions—e.g. resolutions on Cyprus, the Middle East, threats to international peace and security caused by terrorist acts etc.—some of which span across decades of SC practice and seem to be ongoing issues on the SC agenda. The findings of this process suggest that the SC actions are tainted by selection bias, with the vast majority of resolutions addressing issues taking place in Africa and the Middle East. In order to further advance the analysis, for each of the 2,195 resolutions adopted by the SC between 1946 and 2014, the database provides information on which sources of international law—international treaties, customary international law, UN documents etc.—the SC refers to in the text of resolutions.