So...because they've saved some lives, it's fine for them to take some lives?
It's weird, I was under the impression that they took an oath that says "On my honor, I will never betray my badge, my integrity, my character or the public trust. I will always have the courage to hold myself and others accountable for our actions. I will always uphold the Constitution, my community, and the agency I serve."
Not "I will drive around and when my attention is drawn to a member of the public, I will then decide whether they lives or die."