Wrong. The cop IS at fault. Just like in court Thomas' escalation would be used in the mugger's defense.
A cop shooting a man with a knife is not the cop being wrong, not if that man clearly makes an attempt to do harm to that cop. That's what a whole bunch of people (including my fellow black people) would have you believe. A cop shooting a man that makes such an attempt is not escalation. Now, if the man just stands there with the knife, then it's escalation if the cop immediately shoots the man. That's why I said "if the man makes an attempt on the cop's life". Because it's only in that situation where the cop is justified in shooting the armed man. Not only that, but the mugger would not get away with what he did. The mugger pulled a gun on an unarmed man, his wife, and his son. There is no way the mugger would have any defense whatsoever. Because his life was not threatened and he was not in danger. In the case of a guy who is high on meth and holding a knife, if such a guy makes an attempt to kill or otherwise harm the cop, then that guy is putting the cop's life in danger, and the officer is well within his rights and authority to fire on that man. And again, just to stress, this is only IF the man makes an actual, physical attempt to do harm to the cop.
This is not a mere situation of escalation of force. In such a situation, the man wouldn't be making an active attempt to harm the cop. As in that Forcillo case. That situation, I understand what you're saying. But what does the cop do if that person attacks? That's what I was bringing up. If, and only if, that person actually makes an active attempt to use that knife to do harm, then the cop would be justified in using force. A cop would do the same thing if that person was trying to use that knife to harm someone else. And if a cop isn't allowed to do that, then there's a problem, imo.
Either way, I do agree that Thomas Wayne acted rashly and aggressively, but he was not the aggressor. That was self-defense. Failed self-defense, foolish self-defense, but it was self-defense. He was not the aggressor in the situation. The man holding the gun (I assume Joe Chill) was the aggressor. And you can't equate that situation to that of cops who also carry sidearms. That should in no way affect Batman's view of criminals. Joe Chill was not a victim. If anything, he was inspired by his father's attempt to act to save his wife and son. If anything, that is what motivates him to also act. His father's example. Not only that, but you can't just assume that Joe Chill would've spared them had Thomas not tried to attack.