Here's the post I responded to: My limited knowledge of case law, very limited, leads me to believe that if the cop cannot demonstrate Imminent Threat, he's a candidate for Murder II.
My response was that the question of the cop being in imminent danger is the only thing that matters. The robbery at the store is not relevant. Many people on threads on this topic (including this one) seem to think that the cop should/could have shot the kid just for the robbery. That would be an execution.
execute [ek-si-kyoot]
verb (used with object), executed, executing.
4. to murder; assassinate.