The only hard evidence to support claims of massacres at Srebrenica came from a single witness who claimed to have been part of an execution squad. This man, Drazen Erdemovic, was a mercenary soldier who managed to fight for all three sides in the Bosnian war. His mental health was poor, he told rambling and unbelievable stories, but – after initially being judged too mentally incapacitated to stand trial – he became the prosecution’s only witness who claimed to have taken part himself in a large scale massacre of Bosnian Muslims.
Not even Erdemovic’s 7 claimed accomplices to massacre were tracked down and brought to justice, despite ICTY promises that this would happen.
Read the definitive account of Erdemovic’s credentials as a witness by Germinal Civivkov here