"So because the location of the trail would be complex, the security problematic, the costs expensive, death before verdict was likely and you're sure that he would be found guilty it's OK to through justice out of the window and just shoot him?
Er yes, it is ok to just shoot him in this particular case. FWIW I think it depends on your definition of justice. I think justice is served by his execution, given that he has been behind the murder of thousands of ordinary human beings going about their daily lives and caused untold misery to thousands more. Why beat about the bush? (pardon the pun) 
And then there's the tricky concept that with rights come responsibilities, one of those responsibilities being to NOT go round masterminding the killing of thousands of regular people because you hate things some other people of that nation have done. If you behave in an inhuman way, why should you be granted the same rights and dignity as those of us who treat others with respect? Just a thought - and a highly controversial one, I know, but it deserves pause.
"Either justice applies to us all, or there comes some point where a bean counter can say "actually, you're exempt, you'd be too expensive, and we know that you're guilty, so we'll just shoot you and be done with it"
Badger, you have an over-inflated sense of our moral worth as a nation and also a rather too uncritical view of the so called democracy we have here, as laptop suggests. It's not the financial cost of your type of "justice" I'm worried about as the security costs and the potential loss of life that could follow were he kept in custody. The human costs are too great I feel ultimately.
And do you suppose these people care about the example we are setting. They are laughing at us behind their hands and planning the next move.
Badger - your ideals are sound, admireable even. I'm not decrying them - but I just don't think they work and that they would lead to more misery and danger in the long run.
What does it mean to be human anyway?