Honest police may feel it's in their interest. It protects them from false accusations, and from leal and reputational consequences of being associated with dishonest associates. Being honest, they might also want to see dishonest, criminal actions stopped and punished.
Its dehumanizing and eats away at the core of any intelligent person wanting to ever be a cop.
The camera should be on in any situation that might later be a subject of dispute. If it's off in such a situation, the courts should consider that a reason to disbelieve the cop who turned it off. A cop who doesn't possess the judgement to operate a camera, probably doesn't possess the judgement to carry a firearm either.
I subscribe to the notion that cops absolutely need to be held to a higher standard, esp. given their potential for exponentially causing harm (because guns and LE powers).
[1] http://thefreethoughtproject.com/court-police-departments-re...
> Honest police may feel it's in their interest.
Yes. I choose to have a dashcam in my car; it has once proved me not at fault, but if I screw up, it could equally prove me at fault. I think it is in my interest because I think it is overwhelmingly likely that the truth will be in my favour.