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Congratulations to the Legal Tools for Peace-Making Project Team - Prof Marc Weller, Dr Mark Retter and Dr Andrea Varga on the publication of their book International Law and Peace Settlements as part of this project.







Legal Tools for Peace-Making is a three-year Economic and Social Research Council (ESRC)-funded project which aims to give coherence to the burgeoning practice of internationalised peace-making by offering practice-relevant guidance for mediators and conflict parties, while providing important conceptual insights into the nature of this rapidly developing field.

The project is conducted under the leadership of Professor Marc Weller, Professor of International Law and International Constitutional Studies in the Department of Politics, University of Cambridge. Professor Weller is uniquely placed to investigate the field of peace-making, having acted as a legal advisor in a range of international peace processes spanning more than two decades. Recently, this experience has included being appointed as a United Nations Senior Mediation Expert, alongside serving as a senior consultant to the Joint Special Representative of the UN and League of Arab States on Syria (Kofi Annan) and the UN Special Envoy for Yemen (Jamal Benomar).

The current research team, based at the LCIL, consists of Dr Mark Retter and Andrea Varga, while long-time researcher of the project, Dr Tiina Pajuste, continues to provide valuable external advice and contributions. In addition, the project benefits greatly from collaboration with the United Nations Mediation Support Unit (Department of Political Affairs) and the assistance of an Academic Advisory Board and a Practitioner Advisory Board, each comprised of leading experts in peace-making from around the world.

The preparatory phase, conducted from summer 2012 until November 2014, was generously supported by Humanity United and the Newton Trust.

Practical Background

Since the end of World War II, over 1,000 peace agreements have been concluded. This practice of peace-making accelerated with the end of the Cold War. On the one hand, the unfreezing of the Cold War has led to a number of significant settlement opportunities, such as Namibia, South Africa, Mozambique, Angola and Cambodia. Paradoxically, at the same time, a whole host of new conflicts requiring termination broke out, such as those in Eastern and Central Europe, Western and Eastern Africa, the Middle East and North Africa. Much of this settlement practice has addressed internal conflicts, challenging the more traditional approaches to peace-making and peace-building, and resulting in the need for innovative legal approaches in peace agreements.

The UN Secretary-General has emphasised that mediators in contemporary conflicts “have to grapple with a wider range of substantive issues” and that “mediation and facilitation efforts have moved beyond securing a ceasefire and have focused on achieving comprehensive settlements, which deal with a broad range of issues such as, inter alia, power-sharing, wealth-sharing, constitutions, justice, human rights and security issues” (UN Doc. A/66/811, p. 5). However, the extensive experience of peace-making evidenced in earlier agreements is not systematically connected to, or exploited in support of, present settlement attempts. Instead, an ad hoc approach prevails, with each issue to be negotiated having to be researched afresh by the mediation team (assuming the team has the capacity to undertake such an effort). Before Legal Tools for Peace-Making and the Language of Peace research tool, there was no substantive repository of approaches to the settlement of specific issues based on previous practice. The researcher would need to, drawing on their personal experience, trawl through hundreds of peace settlements each time, in order to identify useful previous examples and options.

There is also an unhelpful asymmetry among the parties to peace-mediations in this respect. Governments may have the tools to prepare their positions based on an understanding of previous practice, but opposition groups will not normally be able to engage in the necessary research effort. A lack of understanding of settlement options and relevant previous experiences would often constitute a major obstacle in negotiations, with the inability of non-state actors to articulate their grievances in a constructive and negotiable form.

Conceptual Background

Beyond the practical aspects of peace-making, there is no shortage of academic writings addressing the area in political science and international relations literature. However, beyond some episodic treatments of specific negotiations or agreements, there is a remarkable gap in the treatment of peace-making from a legal perspective. There is no systematic review of the substantive practice of peace-making in its entirety. This project is the first to offer such an ambitious review and assessment of all known practice, and to consider the extent to which this practice is consistent with, diverges from or develops international law.

While the practice has not been thoroughly analysed yet, the proliferation of settlements has in fact given rise to a more conceptual academic debate. It has been argued that a distinct area of international legal regulation - a lex pacificatoria - has been born. This debate is sometimes linked to the claim that a new area of international law governing the post-conflict phase - lex post bellum - exists. For instance, Professor Christine Bell of Edinburgh University states that: "… the practice of fashioning and implementing peace settlements is forcing a revision of relevant international law, as the traditional assumptions and boundaries of the relevant bodies of law do not fit within post settlement political landscapes, are inadequate for enabling and regulating peace settlement implementation and do not contain guidance for the dilemmas faced post settlement." (Christine Bell, Peace Settlements and International Law: From Lex Pacificatoria to Jus Post Bellum, University of Edinburgh Research Paper Series No 2012/16, p. 1)

This general agenda has already found a strong echo in international legal and international relations scholarship. Several international conferences have been held addressing the issue of a possible jus post bellum or lex pacificatoria in relation to areas such as power-sharing and human rights.

In its conceptual phase, this project will investigate to what extent regulation of particular issue areas in peace agreements is consolidating towards the establishment of novel normative expectations. If practice is hardening from policy preference in individual instances of settlement into legal rules, the next question is whether these rules are compatible with general international law. In other contexts, it has been argued that the creation of more and more specialist 'legal regimes' in international law risks fragmenting the unity of the international legal system.

There have indeed been a number of noteworthy clashes between peace agreements and certain areas of international law: notable examples include the Dayton Agreement’s power-sharing arrangements and the prohibition of discrimination in international human rights law, as illustrated by the case of Sejdić and Finci v. Bosnia and Herzegovina, and the controversy as to whether the Lomé Accord’s amnesty provisions could preclude prosecution for international crimes, as highlighted by the case of Prosecutor v. Kallon and Kamara at the Special Court for Sierra Leone. Nonetheless, not all that is normative in peace-settlement practice translates itself into legal requirements. Instead, there may be an accumulation of policy choices driven by relative constellations of power or by convenience. Where these choices translate into emerging legal practice, such practice may extend, rather than challenge, general international law. Where there is conflict between settlement practice and international law, further research is required in order to better understand how the international system can – and does – address such situations.


Against this background, the Project has four distinct, but mutually reinforcing, objectives:

  • presenting, for the first time, the vast practice revealed through peace agreements on an issue-by issue basis, making it instantly accessible to practitioners and academics;
  • deriving from this practice realistic settlement options for use in actual peace-negotiations, and making these available to the United Nations, the African Union, the EU and other mediating agencies;
  • analysing this practice in relation to each issue area against the background of general international law, with a view to identifying advances of, or deviations from, universal legal standards; establishing how the international system addresses possible deviations from universal standards in this area of law, and asking whether we are witnessing the creation of a distinct lex pacificatoria or jus post bellum and how this might affect the coherence and stability of the international legal system.