I do agree that execution is not necessary in most of tghe cases it is used in the United States, especially in light of the millions it costs to get through all the appeals first. It is cheaper just to warehouse them.
And, according to some of the stuff I've read, as many as 10% of convictions are wrong.
What do you do after you've executed the wrong person? Dig him up and apologize?
However, I also believe the Americans have a justice system based on English Common Law, and that they have the right to sentence their criminals as they see fit. I would have no problem extraditing wanted US citizens.
Remember Charlie Ng?
I believe some crimes are so horrendous, so evil in nature, that the perpetrators should not be allowed to live.
Here's my proposal. If some person is suspected of committing mass murder, they should be tried for each murder individually. Different trial, different judge, different jury. After their third conviction, they should be executed ASAP.
Any "not guilty" decision would remove the possibility of execution.
So the worst, the most evil, are not tolerated, but removed. Permanently. With a sort of triple jeopardy clause to protect against wrongful conviction.
Just a thought.