Lemme ask you this. Who killed more YBM? Cops or other YBM?
Aside from presenting no evidence, you are comparing inequivalent things.
When common citizens murder each other, it's usually considered a crime, and the perpetrator, if caught, will go to jail provided that a jury of their peers becomes convinced that they are guilty of that crime.
When a police officer kills someone, it is far less clear whether justice will be possible to attain, and their victim's criminality is assumed despite never having faced the criterion of the law.