Last summer, a New York city police officer choked a black grandfather named Eric Garner to death. Garner was suspected of selling loose cigarettes. The arrests of people like Garner are part of a controversial policing tactic called Broken Windows. Broken Windows claims to prevent large crimes by cracking down on small ones. But it's really about controlling and punishing communities of color, through police encounters that can sometimes be deadly. Commentary by Molly Crabapple.