I don't do conspiracy theories.
Your last sentence could have been said by the relatives. They all but had him hung drawn and quartered before they drew breath.
Well, Lookout. Don't you claim to have insight into peoples' characters? I don't suppose, for a moment, you're the only one. They may NOT have known him well, but they certainly knew him long before the murders, whereas you only 'know' the person he's presented himself as being since he's been in prison.