I favor the death penalty and the host of automatic processes of appeal and review that go with it in the US.... so that to the best of our ability, we avoid executing an innocent person.

I also believe in differentiating between menaces to society v. the one-off act of an "until then" law abiding person.

Each case really must be viewed in isolation. No one over-arching set of rules can cover all circumstances... and that's why juries should be involved in the sentencing of capital murders.