They would end almost overnight, this seemingly everyday habit of our (almost entirely) White police gunning down people of color (mostly boys and men) in the streets of America. All it takes is one short Amendment to the U.S. Constitution.
Proposed Constitutional Amendment
Section 1. Neither any state nor any body of government acting under color of state law at any level, shall appoint, engage, employ or otherwise resort to the assignment of any person of the White race to serve as a police or other armed law enforcement officer of any rank, anywhere within the United States.
Section 2. This amendment shall take place upon ratification, but displaced police personnel losing the right to employment under this amendment shall be afforded up to two full years of unemployment compensation at the same rate and level allowed by their state of residence for any unemployed person, payable until such former police official becomes reemployed outside of law enforcement.
Section 3. Congress shall have power to enforce this article by appropriate legislation.
I can hear you thinking it: "Wow, what a stupid and unworkable idea!". No doubt.
But just consider this: Constitutional Amendment or no, this is still America, and we are still a country full of communities where police violence is tolerated and extolled by vast swaths of the people simply because the police shooting victims are almost always people of color but the community is actually run by White folks, whether they are the majority or not.
If the police doing the shootings, instead, were mowing down people of color, then no matter who got shot, America's White dominated communities would never stand for it. There would be inquests, prosecutions, convictions and lawsuits enough to snuff out this blight on the American character and the deterrent effect would be effective and permanent.
It's completely unworkable, of course. I suppose it would tear the country apart and, anyway, America would never allow such a ridiculous and destructive idea, like, you know, the ERA.