He became a producer for the CBC network program The Fifth Estate from 1989 to 2001, where he covered wrongful convictions, police corruption, war criminals and biker gangs.
Sher played a leading role alongside Daniel Burke and Hana Gartner in exposing Inspector Claude Savoie of the Royal Canadian Mounted Police (RCMP) as corrupt.
His book Somebody's Daughter: The Hidden Story of American's Prostituted Children and The Battle to Save Them was described by Publishers Weekly as a “thorough, deeply affecting study... [that] strikes a rare balance between revealing trauma and hope.”[4] His other book on child safety, One Child at a Time: Inside the Police Hunt to Rescue Children from Online Predators, was described by newspaper reviewers as “riveting” “eye-opening” and “gripping”.
[7] His book Until You Are Dead: Steven Truscott's Long Ride Into History about Canada's most famous murder trial helped lead to an official re-opening of a 40-year-old case and clearing a man who was wrongly convicted.
[9] He has filmed, written, directed and produced documentaries on scandals, wars and corporate intrigue in Afghanistan, Iraq, Lebanon, South Africa, Somalia, Costa Rica, Honduras, Mexico, Holland, France, England, the United States and Canada.