I think it's pretty clear that the vast majority of the people form their opinion of the police based on media reports, not personal contact.
That would have to work both ways though. There may be negative reports today, particularly in the blogosphere and YouTube, but there's a lot more (and always has been) a great deal of TV media splash, appropriately enough called "programming" (a synonym would be 'propaganda'), from Dragnet and Adam-12 through that ridiculous "COPS" show all making the case subtly that such overbearing power trips are actually "normal".
So there's media distortion both ways, and neither extreme represents the whole, but such distortion used to be all one way. And in the mainstream still is.
It is the sensation stories that people see the most, cop shoots man with hands up 9 times in the back, police officers beats teen with clubs as he tries to protect himself, etc. These stories of police brutality and misuse of authority are run over and over, day after day, then repeated over and over with every new development in the story. As any propagandist knows, repeat something often enough and people will believe it. Show a dozen or so brutal attacks by police officers enough times on TV and Internet, people will assume that this behavior is representative of a million law enforcement officers in the country.
,
I don't know that a conclusion of
degree logically follows ("a million") but certainly the events exist, so regardless how many times that guy shot in the back gets replayed/viewed/talked about, it doesn't make it any less true.
Naturally the sensational, the extreme, the outrageous, are going to get the most splash, by definition. There's no particular reason to report the everyday mundane; that's not news. But these extremes DO happen, and they happen frequently, and after a number of samples from far-flung areas and settings, the observer can indeed establish that it's a pattern and it's endemic to the concept of policing, at least as it manifests in these United States -- which is, tellingly, markedly different from how it manifests
outside them.
Personally I'll never feel relaxed in the presence of police, and while that suspicion may be
informed by such reports, it's based direct experience. There's a fatal dynamic created when we combine (a) an authoritarian-worshiping culture of "might makes right" obsessed with guns and violence, and (b) what is effectively an autonomous martial law force, armed to the teeth with military paraphernalia and military mindsets. Its natural result is to create conflict, an "us vs. them" mentality. It can hardly go any other way.