The only thing she actually did wrong was plaster it all over social media. If you believe her story, and nobody does, she claims the dog approached her growling, miles from civilization. I would have shot it too, (again, her story is unlikely, but assuming it's true). If you have a gun and are approached by an aggressive dog, who appears intent on confrontation, any of us would shoot it. If I remember correctly, the aggression angle came about 3 days after the shooting, and about 2 days after she became the most hated person in America.