retrocop - // As I described earlier. Not murder ,state or otherwise, but retribution. //
The two are not mutually exclusive, a murder can be carried out as retribution, but that does not in itself stop the act being a murder.
// Would you describe Mr Albert Pierrepoint as an abominable ,evil ,blood lusted killer and murderer.? //
No because I am not in the business of bolstering my point with unstated and indeed unthought florid language, that is your addition, not mine.
// He despatched with dignity and compassion with no suffering or botches. He was not a murderer. //
According to the Cambridge dictionary, he was a murderer -
MURDER | meaning in the Cambridge English Dictionary
https://dictionary.cambridge.org/dictionary/english/murder
murder definition: 1. the crime of intentionally killing a person.