I think the "and put on youtube" part isn't necessary. Nobody needs to see the footage unless there is suspicion of misconduct.
Such a limited access policy would not be sustainable. Not only would the footage be routinely hacked, but given the supervillan view of cops by many, the same people saying the DA cannot be trusted to prosecute cops, will say no one in government can be trusted to determine what on the tapes is "misconduct". There would be immediate outcry to make all the tapes a matter of public record, which would mean most of it on you-tube tomorrow.
Besides all of that, ask most people if they want their every move and word recorded "but we'll only expose your whole life if any of the many people with motive to harm you make a claim (no matter how baseless) of your misconduct." How many would have no problem with it? Why should we expect cops to feel differently than typical humans?
The problem with this approach is the cops see too many things that don't belong on You-Tube or any public forum.
How I would like to see it handled:
Tapes of any incident are kept for say 1 year, if criminal charges result they're kept until the person is dead or not guilty. Any tape will be kept for a year if a request is made--this can be informal and is uncontestable other than due to abuse (if someone keeps submitting requests and not following up on them they don't get to make any more.) Anyone showing relevance can view any tape. Requests to release them go before a judge if the police disagree. (And they very well might--the video is liable to have privacy concerns.)