We have a problem with the police in the United States being much too willing to use violence. A pair of recent cases where police officers shot and killed other police officers, incorrectly thinking that their own colleagues were dangerous civilians, highlight that issue.
In Texas, a deputy constable was fatally shot by a sheriff’s deputy as the two of them investigated a report that some “suspicious” person had run down the street, leading those police officers to look around the inside of a nearby house. No one else was present in the house besides the two police officers. https://www.kxan.com/news/texas/sheriffs-deputy-accidentally-shoots-kills-constable-in-fort-bend-county/
In Arkansas, police officer threatened to shoot through his door at any hypothetical “protesters” who might show up, despite no such people having ever appeared at his door. When another police officer from his department came to pickup a squad car, the police officer shot through the door, killing that fellow police officer. https://thefreethoughtproject.com/cop-arrested-killed-fellow-cop-through-door/
The death of any human being is a loss, and here we have two entirely unnecessary deaths. That is tragic. What is equally tragic is the fact that both of the police officers who fired were intending to kill (non-existent) citizens who clearly did not deserve to die, which tells us we have a deeply-seated problem with policing.
Looking beyond those two cases, the statistical data shows that our police have become overly-militarized and are much too quick to pull the trigger. Indeed, much of that problem can be traced to the “warrior” mindset problem within American police departments which encourages police officers to treat everyone as deadly threats and to be much too quick to use deadly force against the people that the police officer has sworn to protect. This statistically unjustified hyper-vigilance that pervades police culture is why the above two police above are dead at the hands of their colleagues, just as it is (part of) why so many innocent Americans have been killed by the police. The Harvard Law Review published a most excellent article on this “warrior” state of mind problem: https://harvardlawreview.org/2015/04/law-enforcements-warrior-problem/
Beyond that, even adjusting for different rates of violent crime and different population levels, the inescapable fact is that police in the United States shoot and kill more frequently than in any other developed nation. A good overview of that can be seen here: https://www.afromerica.com/afrone/american-police-shoot-kill-and-imprison-more-people-than-other-developed-countries.
Finally, for a discussion on the issues with police brutality and racism between the police and citizens, please see these links: