The worst people at concerts, from self-involved selfie takers to nonstop filmers

A man posthumously identified last week as a serial killer, who police believe is responsible for three cold-case murders in Ontario in the 1980s and 90s, had a history of committing violent crimes, including rape.However, Kenneth Smith remained biologically off the radar of law enforcement for decades, police say, because his prior convictions occurred before the creation of both the national DNA data bank and the sex-offender registry.