When can you? That's the question that a Florida woman must be asking. According to the Washington Post:
Yesterday … an alligator walked through the doggy door of a woman's house in Bradenton and went for her golden retriever. The woman grabbed a shotgun and blazed away. The alligator escaped with a flesh wound. The neighbors heard shots and called police, who promptly cited the woman for hunting without a license.
It's legal to shoot a person who invades your home, but apparently defending your pet against dog-eating alligators is verboten.
Another hat tip to Pamela Friedman.