Make the Double Jeopardy law not apply to people who admit to having done a crime after the trial is over.

I beleive that the Double Jeopardy law is good for those innocent, so that they are safe from being tried more than once.
But the people who might have admitted to doing a crime after a trial should not go unpunished because of that law.
The law should be repealed and made so that people who admit to doing a crime are punsished, but the innocent will stil be safe.