He has used Darwinian theory to explain antisocial behavior and actuarial methods to predict it.
He earned a bachelor's degree summa cum laude from the University of North Dakota in 1966.
He joined the staff of Penetanguishene Mental Health Centre in 1971 and was appointed director of research in 1976.
In 1984 he spent two years as a visiting scientist at the Institut Philippe-Pinel de Montréal and adjunct associate professor at Concordia University.
He held an Ontario Mental Health Foundation senior research fellowship (1997-2003).