Correct, police have no statutory immunity from criminal prosecution, except where a statute explicitly states it (a few statutes say "Except when committed by a peace officer in his lawful duties" etc).

OTOH, judges are mostly ex-prosecutors, and if I were this cop I would take a bench trial and gamble on the judge acquitting me regardless of the evidence. As one judge said to me, on the record, "police officers are allowed to commit crimes to gather evidence."