The public notion of good policing and the actual practices police departments follow have been diverging for several decades (if they ever converged). What we're seeing right now is not some inexplicable increase in bad behavior or cops deliberately targeting journalists. For modern American police this is just business as usual, except the volume of deployment is significantly higher than in the past few decades and the visibility is much higher as well.
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There is a flip side to this coin. When you have a systemic problem of this scale, you should be cautious about making simplistic (especially moral) judgements about individuals in the system. When someone's training, incentives, position in the community and even equipment nudge them towards bad actions, even decent people will routinely do bad things.
"There's a reason you separate military and the police. One fights the enemies of the state. The other serves and protects the people. When the military becomes both, then the enemies of the state tend to become the people." - Commander Adams (Battlestar Galactica)
Obviously, this doesn't directly address the militarization of the police, but it should be easy to see how it can go both ways. Outfit the police as a military unit, and they'll start acting like one. How much surplus military equipment was sold to police since the Iraq war?
- Hannah Arendt
> This drug thing, this ain't police work. I mean, I can send any fool with a badge and a gun to a corner to jack a crew and grab vials. But policing? I mean you call something a war, and pretty soon everyone is going to be running around acting like warriors. They gonna be running around on a damn crusade, storming corners, racking up body counts. And when you at war, you need a fucking enemy. And pretty soon, damn near everybody on every corner is your fucking enemy. And soon, the neighborhood you're supposed to be policing, that's just occupied territory. You follow this? [..] Okay the point I'm making is this: Soldiering and policing, they ain't the same thing. And before we went and took the wrong turn and start up with these war games, the cop walked a beat, and he learned that post. And if there were things that happened on that post, where there be a rape, a robbery, or a shooting, he had people out there helping him, feeding him information. But every time I came to you, my DEU sergeant, for information, to find out what's going on out on them streets... all that came back was some bullshit. You had your stats, your arrests, your seizures, but don't none of that amount to shit when it comes to protecting the neighborhood now, do it?
- Howard "Bunny" Colvin in "The Wire"