WASHINGTON — D.C. police are investigating after an officer shot and killed a dog that allegedly attacked him while serving a search warrant at a Northwest Washington home Tuesday night. Marietta Robinson, who lives at the address, said police were unjustified in killing the dog, which she put in the bathroom before police entered the home. Police were searching for her grandson, who the woman said hasn’t lived there in so long, not even her 13-year-old dog knew what her grandson looked like. An officer entered the bathroom over the 62-year-old woman’s protests and shot the dog, named Wrinkles. As...