Not to trivialize this too much, but with regards to weapon use on crowds I'm really struck by the parallels to AMERICAN FOOTBALL (fuck yeah). The NFL is currently in a very tricky situation trying to legislate player safety while trying not to admit too much knowledge and liability to former players and juggling complaints about rule changes from fans, analysts, and players. A large part of the issue is that because their current pads and helmets are so protective the players perform more dangerous actions and cause more and worse injuries. I can't help but think major police departments are going to end up doing a similar juggling act within the next few years as they try to deal with some of the highly publicized fallout from their weapons tactics.
Though I'm not optimistic about how the process is going to start. Seattle's police department is under heavy Federal critique about the percentage of their use-of-force cases which escalate to being Constitutional rights infringements. The more enlightening bit of the report (that, of course, is being mostly ignored) is that a small subset of officers are responsible for a hugely disproportionate amount of these. Instead of doing the sensible thing, like, say, discipline or fire the offenders and leave the vast majority of your police force intact, not only the union but the police chief have made a lot of noise about contesting the results.
I'd been looking for a way to bring this up earlier during some of the more heated attacks on the concept of a police force, but I really do feel like just the elimination of the thin blue line would solve the vast majority of police abuses in the country. It makes it hard to defend the good police officers when even most of the best ones feel some sort of obligation through their bonding in a dangerous career to defend their fellow officers no matter what they're actually doing. That and maybe screen veterans for PTSD or something radical like that.