> black Americans have been claiming that such things happen and were widely ignored or disbelieved
Black Americans commit a wildly disproportionate amount of crime. Black men make up 1 million out of 2.3 million people in prison. 4.7% of all black men* are in prison. A black man has a 70% chance of being in prison at some point in his life. Are you suggesting the police are framing all of these people?
While police conduct exists and is deplorable, my sense as an observer is that the majority of black anti-police activism is about somehow pinning the criminality of the black community on society at large.
While I of course condemn polite misconduct, I can understand how repeated interaction with a recalcitrant criminal element could harden and corrupt a police officer.
Look: if we're going to have a productive public conversation, we need to acknowledge that black arrest rates are in part a result of elevated black criminality and not pin the entire problem on the police.
Downvote me all you want: it won't change the facts. Ignoring facts and making policy according to utopian fantasy has never led to human progress, but it has led to a great deal of misery.