1983 would be against the Sherrif for false arrest and imprisonment. As soon as it became clear that they did not have the appropriate mens rea for any of the crimes holding them in jail was blatantly illegal. Even if you somehow manage to misinterpret the law to not require mens rea, as soon as it became clear that it was entrapment it became illegal to continue to hold them.

There is no reasonable legal theory in which they are not innocent, unless there are substantial non public facts.

That's whether or not you think that the state has the authority to authorize this.