I kinda agree with dingo.

However in my head surely an option would be to either give them the option of doing it themselves.

"I hereby sentence you to live in prison, for a minimum of 55 years, with nothing but a 13 foot long legnth of rope".

I was trying to find a way to use the famous phrase "Let him hang himself", bu i thought it was too obvious.

I dont think i agree with it, even though a few people deserve it, as surely life picking up soap is worse than a quick, painless, injection