For dealing with former human rights violations post-conflict societies have several choices. Besides criminal prosecutions truth commissions have been set up since the mid 1970 to find a way for reconciliation between perpetrators and victims. This paper focuses on the analysis of truth commissions with a significant time span to the transitional period in a comparative manner and asks for the causal mechanisms linked to it. To explain the time lack hypotheses are tested on the balance of power, civil-military reforms and the degree of human rights violations. The analyses for the truth commissions in Uruguay, Ghana and Panama indicate that a lower degree of human rights violations and the elections of political leaders and parties closely linked to the authoritarian era foreclose the establishment process. These results are controlled by the analysis of truth commissions in Argentina, South Africa and Haiti that were directly set up after the transition. Further it is argued that civil-military reforms have no influence on the establishment of truth commissions and that the balance of power is not levelled as is argued in the literature.