In recent years the international community has been witnessing the establishment of a number of international and local courts with the intention to prosecute individuals that have committed serious crimes against humanity during war. It seems evident that post-conflict tribunals can work as a deterring factor and as a moral justification to victims of war crimes. Still, these processes have been met with skepticism from academics as well as politicians, suggesting that the warring parties’ fear of prosecution after conflict can prevent them from laying down their weapons and cease fighting. In this paper it is, however, suggested that it is necessary to distinguish between reaching a settlement and creating sustainable peace. Amnesty and exiles to wrongdoers can be an important part of peace negotiations and settlements, but the more long-term post-conflict peace building process may benefit from wrongdoers being punished and victims of war compensated. Building on a newly constructed dataset (Binningsbø, Elster & Gates, 2005) reporting the presence of various forms of post-conflict justice efforts (trials, purges, reparation to victims, and truth commissions) – as well as processes associated with abstaining from post-conflict justice (amnesties and exiles), starting with each conflict in the Uppsala-PRIO Armed Conflict Database, the long-term effect of post-conflict justice on the duration of peace after conflict is investigated. In doing so the authors are, however, aware that not all post-conflict processes are fair and just, and that the concept of justice is somewhat compromised. In an attempt to distinguish legal justice from political justice we therefore conduct an additional analysis, focusing on the durations of peace only in post-conflict democratic societies. We rely on a Cox proportional hazard model to investigate the influence of the various types of post-conflict justice on the length of the peace period before a violent conflict eventually reoccurs. Our expectations are, however, only partly supported. We do find post-conflict trials as well as other types of justice lead to more durable peace in democratic as well as non-democratic societies, but the results are weak and therefore difficult to generalize.