The footage showed how car thieves tended to walk erratically and look in directions irrelevant to their path of travel. Before an act of violence culprits would walk aggressively, their arms static by their sides, taking long purposeful strides.
Mind you, it's only a matter of time until what the cameras look for is figured out, and tips on spoofing them start circulating on the underworld grapevine, becoming known to every competent criminal and writer of contemporary fiction; and so the arms race begins.