Gun owners and self-defense advocates are lauding a rare victory in which a Texas grand jury has refused to indict a homeowner for shooting and killing a police officer who entered his home unannounced in the middle of the night. The homeowner, Henry Magee, 28, said he thought the officers who broke through his door were robbers and he acted in self-defense to protect his pregnant girlfriend and two children. Police were acting on a tip from a criminal informant that led them to believe Magee had more than a dozen marijuana plants, all at least six feet tall, in...