More than 15 years ago, the Good Friday Agreement came into force - bringing an end to three decades of violence in Northern Ireland. At the heart of the peace process is a commitment to bring truth and justice to the bereaved. But many families say they're still waiting. The peace process also promised to bring Protestants and Catholics closer together. But, in some communities still divided by peace walls, there remains a deep mistrust of their neighbours. So have politicians failed in their promise to deal with the legacy of the past? And how much do we really know about the deals that have already been done to protect people from prosecution? BBC correspondent Chris Buckler investigates. Producer: David Lewis.