The Federation doesn't use prisons except to hold captured criminals prior to treatment. As far as criminal behavior goes, it's treated as a psychiatric disease, and prisoners are "patients", sentenced to rehabilitation therapy. It's likely that Maxwell was sentenced to therapy for 6+ months or so (the same sentence Garak received for attempting genocide against the Founders).
OK, so there are penal colonies, where Tom Paris was serving time, but it makes one wonder whether penal colonies are simply where people stay while they're being treated.
So it's possible that Maxwell would've been released long before the Maquis movement started, but would he have joined after his therapy?