well, my first inclination upon reading this was, execute him.
then I read your comment and thought, "that's probably what they'd do to him in a Muslim country."
Here, he's guaranteed due process (it's a check and balance against unjust power. with it, yes, some scumbags seem to get lucky. Without it, well, think of the torture rooms for dissenters). And a jail that has bars on the windows.
Ironic, isn't it? Must take the bad that comes with the good.
Ask me if I care if some dirt clod who raped 7 American girls and women, and happens to also be here illegally, gets due process.