independent - voted death penalty, which I would like to see as the sole punishment for murder, but like the constitutional standard for treason, only if two or more witnesses can be provided. (Forensic evidence would be counted as only one witness, no matter how many people present it.) A lesser conviction, either for manslaughter, or with only one witness should have the punishment be life without parole, and the jury should be given the option to find that only one witness was credible, thereby making the defendant ineligible for the death penalty. Neither rape nor pedophilia, as horrible as they are, warrant a death penalty on their own, or as special circumstance that makes a homicide a capital offense.
I would go with something like this. Basically, for a defendant to be eligible for the Death Penalty, guilt must be proven beyond any competent(more than reasonable, no one without a moral or mental defect, even if they are strongly biased against a finding guilt, would doubt the guilt) doubt.
The crimes that should warrant it should be treason, terrorism or some sort of heinious premeditated murder for any other reason which, in a single criminal episode or over several criminal episodes, causes the death of 10 or more people.
All this being said, there should a limit of one appeal for the death penalty and upon sentence, it must be carried out in 5-10 or the sentence is commuted to life without parole.
However, there should be alternatives for murder and other crimes that traditionally warrant the death penalty besides just recieving life with or without the opportunity for release. Perhaps for heinous sex offenses that don't involve permenant death or disability of the victim, the defendent may be released after a reasonable period of years if they comply with an order of a definite period civil commitment and agree to undergo radical surgical castration (removal or all sex organs and sexual characteristics).
The point I am trying to make is that its not a legitmate interest of Government to settle personal blood feuds. It is a legitimate interest of Government to protect macro-level Security.