Are police officers allowed to swear at you?

First of all: The police didn't just, "...show up to complain." You can bet your life that one of your neighbors did the complaining, which brought them in reponse to a "nuisance" call. That being said, by departmental regulations and codes of conduct he probably should not have cursed at you, or about you. But (here's a shocker for you) cops are human too. He may even have kids or a sister your age and after what he observed at your home he simply "lost it." Count your blessings that he didn't bundle you off to be handled by the Juvenile Authorities or perhaps, even arrested you.