smooth

it's not.
prohibitions against ex post facto refers to punishments in criminal law, anyway.
courts are pretty fast and loose on what constitutes "punishments" too. challenges to sexual offender notifications and registrations laws on the basis of them applying to people who had been convicted decades before were struck down for some dumbass reasoning that registration is not an additional "punishment." never mind the poor drunk frat boys who now have to register for peeing on their neighbors rosebushes and whose job chances severely diminished for the rest of their lives :\

basically, they could have written it to strip all legality from homosexual marriages past, present, and future, but they didn't for whatever reasons.

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