In Arizona Board of Regents v. Harper, 108 Ariz. 223, 224, 495 P.2d 453, 454 (1972) seven students sued the Board for a declaration that the one-year residency requirement was unconstitutional. After a bench trial, the trial court found that the students were residents, "had been improperly charged nonresident tuition," and the residency requirement was unconstitutional; and it thus ordered that the students were entitled to a refund. Id. The supreme court reversed the trial court's determination and found that the non-residency requirements were constitutional. Id. at 226-31, 495 P.2d at 456-61. There is no hint in Harper that the Board was immune from declaratory judgment actions.