In 1992 some LAPD cops got caught beating a poor black person named Rodney King on camera and were later acquitted. The mass indignation felt by LA's poor at decades of police violence and torment (and other things I'm sure) exploded into a massive riot that lasted for a week.
This question makes me think: was it the videotaped evidence of police violence that caused the uprising, or was it the pent up anger that built for such a long time?
If cops are monitored via this technology, I think it might reduce cases of 'exceptional', brutal violence, but it will not eliminate them. The police as an institution attracts people who want power over others. Liberals make the 'not all cops are bad' argument because even they are aware of the existence of such sociopaths.
If you look up on youtube cases of police violence, you can find a whole bunch of them, but their release into the public hasn't stopped such cases from happening. Not to mention that these instances didn't cause their own Ferguson or LA, they were noticed by a few people who already don't like cops and have probably been forgotten by most of them.
So it's entirely possible that the existence of body/dash cams will simply NORMALIZE police brutality. It might even normalize how casually violent they are during simple arrests (something many people have the privilege of being unaware of). This possibility follows the 'LA riots happened because of pent up anger collectively released' train of thought. The release of the video footage was only PART of the reason why revolt happened. The pent up anger was the real vehicle for all that.
At the same time, if momentum continues from what's happening in Ferguson, then perhaps such video evidence will allow for further revolt.
EDIT: I talk about revolt not as an opportunist spin on peoples plight at the hands of the police. Being an anarchist, I view revolt and the threat of revolt as the only thing that causes society to try to appease us, to 'throw us a bone.' (which comes with its own questions, read dot's answer above).
