A bad move?

So a man has been convicted of a murder of which he had been previously acquitted, thanks to a new law ending the long-held double jeopardy principle which says you can't be tried twice for the same offence. Much understandable rejoicing by the family of the victim, but there's an old saying "hard cases make bad law", meaning that when you bend, or even worse, change the law to produce what you perceive to be justice in a particular case, you have to bear in mind that English law is founded on precedent, and that the change you have made will have repercussions well beyond the case in question. I hope that, sometime in the future, we don't regret what we have done.