Lawyers for a Colorado man who fired a semi-automatic rifle at the White House last year will argue that their client is innocent because he is insane. The Washington trial of Francisco Martin Duran, 26, began today with jury selection, as defense attorneys grilled potential jurors on their feelings about gun ownership and mental illness. Opening arguments are slated to begin Monday. Duran has been charged with attempted assassination, assaulting Secret Service agents, possession of a firearm during a violent crime and destroying federal property. He pulled the rifle from under his trench coat on the sidewalk in front of the White House in October and started shooting. Tourists pinned him down until Secret Service agents made the arrest.