This shit has been building up for generations. Since long before Martin Luther King, Jr. and Malcolm X were even born. I'll be blunt: for the past century and a half, it has essentially been a crime, in America, to be black. Its a crime to be Hispanic. Its a crime to be poor. Its a crime to be gay or transgender. Why? Because the law does not behave the same for us as it does for the well-off, straight, white man. Fuck, I'll tell ya a little fuckin' story. Cozy up motherfuckers.
When I was a kid, around middle school age or so, my uncle visited us to help fix our AC. The details have gotten a little faded with time, but while my uncle was standing not two meters off our driveway, he got into an argument with a man from our neighbourhood. The man in question decided to stab my uncle. In broad daylight. In front of myself and the rest of my family. Our family lived within easy walking distance of both the local police station and the biggest hospital in the state. Now, you might be thinking that the cops and EMS rushed to the scene and all was well.
It would've been, if we didn't live in a poor, predominantly black neighbourhood.
Prolly the only thing that kept my uncle from bleeding out was his Army training. It took police and EMS over 20 minutes to get to our house. Let me remind you that I could've walked to either location and back in that time. The police took our reports and proceeded to halfheartedly search the area. The only reason they caught the guy was because the Mensa candidate decided the best place to hide would be the alleyway behind our house. My uncle survived, thankfully, and the guy that stabbed him did jail time, but the lackadaisical response we got to, again, my uncle literally being stabbed in the stomach in broad daylight, just goes to show how high a priority for them we weren't.
And that's not the only time people in our neighbourhood got fucked over by the cops just deciding it wasn't a priority to respond to calls from a specific area. Gunshots were a common enough occurrence that I could sleep through them before I'd hit double digits. I lived right across the street from an actual, factual crack dealer that never got so much as a stern talking-to from the 5-0.
All this is far from isolated; its all over this damned country and has been going on for generations. This is why gangs exist. This is why riots happen and vigilantism starts cropping up. When people feel that the justice system society has built no longer works in their best interest, they will start enacting their own justice, even if that justice is violent and scattershot in its implementation.
Fix the justice system and this shit wouldn't happen. Punish officers that murder innocent people. Investigate all uses of lethal force thoroughly. Murder is murder no matter who does it. No one is above the law, especially not the men and women who enforce it.