Attempted cop killers do not deserve a memorial. Vandals will be idiots, but I have no sympathy. Sorry.
Charging someone is attempted murder? I guess so.
Officer Wilson, with his keen eyesight, identified Brown as a suspect in a petty robbery, blocked Brown's way. At this point, Brown allegedly scuffles with Wilson and a shot is fired. Brown runs. Wilson chases. When he no doubt screams stop at Brown, he turns around and Wilson fires. Because Brown allegedly charged him running towards a gun pointing at him.
Use some simple rational deductive reasoning. Wilson believed Brown was a charging demon and shot his gun 12 times, killing Brown. What did Brown have to say? We'll never know.