How does a police officer decide whether to shoot an armed man with an injured hostage? A follow up to our story this week about Triffie Wadman's murder 12 years ago and constable Krista Fagan... the first officer to arrive on the scene. We speak with a professor of psychology at the University of Regina who's also the scientific director at the Canadian Institute for Public Safety Research and Treatment. (Anthony Germain with Dr. Nick Carleton)