Michael Howard – he used to be totally in favour of the death penalty until the Guildford 4 were found not guilty when he realised that they would have been hung despite being innocent.
He publicly changed his mind on capital punishment after that,
I think changing your mind is one of the most interesting things someone can do, you don't need to think to have an opinion, but to have changed your opinion shows thought, or understood, or witnessed (perhaps). But I would only say Michael Howard could be admired for his cameo in Dawn Penn's version of 'You Don't Love Me (No No No)'