An addendum to this - we spend millions every years protecting rapists and child molesters inside prison.
The reason?
Well - simply put, if the other prisoners look down on you for killing your wife a good way to mitigate some of that is to "execute" a "nonce".
The irony being that whilst many in the UK would probably call this Karma (not publicly, of course) we can't allow these monsters to be killed in prison because that's not the sentence handed down and letting it happen would make a mockery of justice.
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