Interesting. You're right about the gap between civil and criminal law, but I can't think of any examples of someone going after civil liability for something that happened in the past under the legal reasoning that a law passed after the act makes the act one a person can be liable for. Can you give an example?
>>shadow+(OP)
Not exactly the same, but the legislature retroactively extended the statute of limitations for sexual abuse lawsuits. Not a case of a newly illegal act, but a case where someone who was in the clear for a past act became liable again.
>>shadow+(OP)
A good example is the post-9/11 lawsuits filed against foreign governments that were enabled by passage of JASTA or liability for asbestos which was broadly enabled by legislation.