To put this in perspective there are more deaths per year in the NYPD than all of UK, Iceland, Japan and other countries that are used to make non equivalent comparisons.
The police do indeed do wrong things sometimes, but to imply that the higher rate of citizen killings here is due to some police malfeasance or conspiracy is indeed tinfoil hat.
I don't think it's naive not to be a conspiracy theorist. Sure, there are some cases of police murders and other misconduct but it's hardly the norm and it is rather spurious to think every run-in with the police lurks the head of a grand conspiracy or a cover-up.
When you watch the news in the US from the UK, keep in mind that many have a vested interest in telling a certain narrative.
The various news sources in the UK have no reason to attack the US police; i'm not sure where you get that from; perhaps it's something you say when someone receives information you don't agree with or find damaging to your beliefs. Statistics; simply the number of dead; don't really lend themselves to much to "narratives".
Watching the news in the US from the UK, it's pretty clear that you (in the states) long ago reached the point where it's not even paranoia any more. The police there killed more civilians in a few weeks of the year than the UK police have killed here in hundreds of years. They murder and lie about it; it's going to be interesting to see what happens now that it's routinely caught on camera, but to suggest that there's anything tin-foil-hat crazy about suggesting that the police might have done something wrong here which has resulted in someone's death betrays a naive (at best) comprehension of the situation there today.