Also, if we assume Fulton County Jail owns the copyright, could they sell mugshot merch? If yes, that’s horrifically dystopian. If no, are they entitled to claw back any money made from the sale of mugshot merch?

They could sell mugshot merch from the copyright perspective, but there would be a load of other issues that would prevent them from doing so.

But technically, they could sue whoever is responsible for selling them and could claw back profits and damages, as this was undeniably copyright infringement for large-scale commercial gain. Look at this: Up to five years and up to 250k per offense. And that’s only the punishment. The damages are between 750 and 30k, 150k if it was “willful”. Plus all the usual stuff like paying lawyers and courts. The Sheriff’s Office down there could buy their own donut factory from the proceedings…