Why might that be?
So, when forbidden- by your attacker- to use the one tool that could kill him in one simple stroke, what do you do? You certainly don't claim that this makes him right. You point out that this is because he knows beyond a shadow of a doubt that he is dead wrong. He knows he is the bad guy, and he can't win unless he rigs the "game".
All legitimacy is lost.
(Ironically today, December 15th, is Bill of Rights Day.)