To this day, Wallace's full role on behalf of the Army remains a mystery. Former members of the Special Forces admit that Wallace worked with them as far afield as Berlin and the Oman during the Cold War, but the Ministry of Defence and the Intelligence Services still try to distance themselves from what Wallace was doing in Northern Ireland. He had been part of the Army team preparing for the Widgery Tribunal into the Bloody Sunday killings of protesters in Derry, and in 2002 he testified at the Saville Inquiry into the events.