Larrikin Larry
A criminal in XXXX who inadvertently contributed to the exact science of execution by hanging, by providing a graphic demonstration of what happens when the length of rope is too long and allows an averagely-sized bodily mass to fall too far under its own unsupported weight.
In layman's terms, his head flew right off and there was a bit of strife.
Annotation
There is a lovely scene in Tom Sharpe's Riotous Assembly where the local Bishop, arrested as a Communist terrorist by demented BOSS secret policeman Verkramp and sentenced by an equally lunatic judge, is desperately trying to teach the stand-in hangman, the psychotic and stupid Konstabel Els, how to do his job, from a mutual knowledge-base of zero. The bishop is extremely concerned that execution for him will mean inadvertant decapitation.