I'm generally against the death penalty, but I wouldn't mourn Dupas or Peter Scully being fed to a pack of rabid dogs.
If the death penalty were to be introduced, "beyond reasonable doubt" wouldn't suffice. There couldn't be any doubt whatsoever.
You could argue life without the possibility of parole is a kind of death sentence anyway.
The black guy in the video I posted above got 170 years for double homicide has been in jail since he was 15.