International humanitarian law (IHL) has traditionally been seen as a legal framework regulating armed hostilities, having little to do with peace. However, recent peacemaking and peacebuilding practice has consistently relied on IHL to frame peace efforts, mainly in non-international armed conflicts. This article explores the relationship between IHL and peace, looking at practice in Colombia, where IHL has been used in a creative way as a means to build trust, facilitate peace negotiations and enforce the resulting peace agreement. Looking at this case, the article offers general insights on how IHL can facilitate the end of conflict and reintegration, frame accountability and reparation, and shield peace deals under a framework in which both State and non-State actors can find a common bargaining zone in their search for peace.

Common Article 3 to the four Geneva Conventions encourages the parties to a non-international armed conflict to bring into force international humanitarian law provisions through the conclusion of special agreements. Since armed groups are ever more frequent participants in contemporary armed conflicts, the relevance of those agreements as means to enhance compliance with IHL has grown as well. The decision-making process of special agreements recognizes that all the parties to the conflict participate in the clarification and expansion of the applicable rights and obligations in a way that is consistent with the principle of equality of belligerents. This provides incentives for armed groups to respect the IHL rules they have themselves negotiated. However, even upon the conclusion of such agreements, it remains unclear which legal regime governs them. This paper will argue that special agreements are governed by international law instead of domestic law or a sui generis legal regime.