You can't apply the law retroactively. There are ... some exceptions. Pardons can be granted (presidential or gubernatorial) for those convicted of specific v

You can't apply the law retroactively. There are ... some exceptions. Pardons can be granted (presidential or gubernatorial) for those convicted of specific violations, or under procedures later discredited. This doesn't of itself provide the ability to prosecute bad cops / bad prosecutors, but does at least undo some of the damage. E.g., President Biden has given broad pardons for marijuana possession under US and D.C. (administered by the Federal government) law: <https://www.npr.org/2023/12/22/1221230390/biden-pardons-clemency-marijuana-drug-offenses https://www.npr.org/2023/12/22/1221230390/biden-pardons-clem...> This doesn't include state convictions for drugs possession (the vast majority of such convictions) but does signal to states which direction the Federal government is leaning. But your damage control is within reach.