no and no
I would never want to see someone put to death over a "all evidence points to it" type of case, but when you have the guy for sure, and everyone knows it was him, Id have to say Id buy tickets to the execution. He needs to be made an example of. A slow painful humiliating death.
If you think he'd ever mull it over in the decades to come of expensive imprisonment and think one day "What a monster I was, Im so sorry, this is so painful to me I wish I was dead!" you are crazy.