When James Craig was a young man in the 1970s, he says law-abiding people wouldn't dream of carrying guns. But then he left town to pursue a career in policing. In the years he was gone, Michigan liberalized its gun laws, making it easier for people to get concealed-carry permits.
When he came back to become Detroit's police chief in 2013, he found a whole new reality.
"You would have thought, given the dynamic of people who carry weapons, that we were maybe in Texas," he says. "But in fact, we were in Detroit, Michigan!"