"By using this logic then, you would wait until a murder is committed instead of intervening while it is in the planning stage?
I stand behind my previous comment that this is one side of the story told by the family. The cops may be guilty as hell of using poor judgment, but they are still inoccent until proven guilty."
I agree. In this case, the murder could have been stopped by having arrested all the cops before the incident happened, or by throwing a flashbang into their "planning room" session, then shooting each of them three times, just to make sure that they didn't go forward with their murder.