Coltart played an instrumental role in the first detailed investigation into the genocide committed by the Mugabe regime in Matabeleland between 1982 and 1987. He initiated the project as Director of the Bulawayo Legal Projects Centre, one of the operational arms of the Legal Resources Centre in 1990. This culminated in the publication in 1997 of the report entitled "Breaking the Silence: Building True Peace" by the Catholic Commission for Justice and Peace in Zimbabwe and the Legal Resources Foundation. The publication of the report led to Coltart being publicly criticised on national television by Robert Mugabe in February 1999, who stated that: