Vested right means that the Court created a right and the legislate cannot take it away. I believe Muniz did NOT CREATE any rights. It only enforced EXISTING rights. So I believe challenging Act 10 of 2018 on vested rights grounds is a losing argument.
Everything hinges on is Act 10 of 2018 civil or criminal in nature. As long as Act 10 of 2018 is civil, they can do what they do all day long.
Also, saying 631 is 1952 is misleading at best. 631 was combined with 1962.
I agree there is a question of whether combining the 2 bills violate the single subject rule. Saying both bills deal with Sex Offenders is not good enough. One is about probation the other about the registry itself.
Remember. Muniz enforced EXISTING rights and did not CREATE any rights. Thus no violation of the vested rights doctrine