I’m generally supportive of body cameras for cops for the reasons cited by lanzacash above. That being said, there are civil liberties implications associated with what could theoretically be, or become, generalized surveillance using body cameras. We have seen backlash to traffic cameras, swipe mechanisms at gas stations, etc. Tere are sensible rules that could be put in place to minimize this concern (e.g., the camera only goes on when the cop is interacting with someone, and cannot be rolling as he’s sitting in his car checking his emails, or buying a coffee). Nonetheless, I suspect there will be some who will eventually come to argue that this is just another method of guaranteeing surveillance of communities that believe themselves to be en masse viewed as “suspicious” purely because of their race, or socio-economic status, by the police.
IMO, the benefits, including from a civil liberties perspective, greatly outweigh the disadvantages. However, it is worth noting that there will be criticisms of what is proposed as a mechanism for protecting civil liberties and ensuring justice is better-served that are also civil liberties-based. And presumably, opponents of the proposal to mandate body cameras (I assume these will include police unions) will exploit those arguments in their advocacy opposing them.