[alricb]

It depends on whether the cameras are just for show (like most CCTV cameras) or whether the authorities actually care. In the Rialto experiment, the police chief was running the experiment as he was doing his master's degree with a prestigious university.

In places with a long and proud history of police brutality, with a tradition of covering it up at the top levels, the cameras are going to be bought just for show. Soon after officers will realize this and go back to their old ways.