From Peru to Canada to East Timor, following periods of serious conflict or gross human rights violations, societies often look to address the past in order to bring about greater accountability (trials), reparation (victim compensation), and truth (truth commissions). To date, more than 40 truth commissions have been established around the world, with the South African Truth and Reconciliation Commission being the most well-known example. Generally speaking, truth commissions are officially sanctioned, temporary, non-judicial investigative bodies designed to produce a final report describing the patterns of violence and abuse, its causes and consequences (Hayner 2011 at 11-12). They do this by taking, collecting, and analysing statements from victims, witnesses, and perpetrators, holding public hearings, carrying out exhumations, and researching and investigating allegations of wrongdoing. The claimed benefits are wide-ranging: disclosure of the truth, creation of an historical record, promotion of national healing, individual catharsis, and acknowledgement and redress for victims. While there is debate about whether truth-seeking processes can deliver these benefits, they may be able to pay greater attention to social justice concerns than criminal trials or reparation processes can. In this blog, based on a recently published chapter in the book The Global Impact and Legacy of Truth Commissions, I explain why truth commissions, while contributing modestly to achieving social justice through their structures, processes and outcomes, cannot in themselves achieve these goals.