The death penalty was rarely if ever enforced in Jewish law. The axiom was that if a Jewish court sentenced one man to death in 60 years it was a ‘murderous’ court.
Because the rules of evidence are so demanding (no confessions, no circumstantial evidence, two witnesses to the same overt act, etc.). But if all the criteria were met the person had to be executed. Not to do so would have been to violate a mitzvah and invite Divine punishment.
The only difference I am aware of between Jewish and Noachide rules of evidence is that for the latter only one witness is necessary.
At any rate, I am both a Theocrat and a Theonomist. We all knew that. I am simply commenting according to my conscience.