This one is Freeman v. Morris (D. Me. Dec. 7, 2011), which dealt with the Occupy Augusta encampment. As with the other cases, the court held that the Supreme Court’s Clark v. CCNV (1984) decision is dispositive. Clark also involved people claiming a right to demonstrate in a park by putting up a tent city that they’d occupy for an extended time; the Court rejected the claim, holding that a Park Service rule banning camping in such parks was a constitutionally permissible content-neutral restriction on conduct. That’s pretty closely on point, as courts have rightly concluded.