My problem with it is this. What if this turns out not to be him?
What if this were somebody else, or even a hostage? You can't just say "Oops, sorry." and have that person magically come back to life.
What if (Gasp!) the Media and the Police are wrong and we find out later this guy was framed and innocent? ''Oops, sorry." again? It won't bring him back to life.
We have trials for a reason. Just to anticipate a counter argument,"he could have just surrendered and lived". If they were willing to burn him out, burning him to death in the process, there is no way you're going to convince me someone's finger wasn't going to pull a trigger.
Gaily bedight, A gallant knight In sunshine and in shadow, Had journeyed long, Singing a song, In search of El Dorado