Answer:
Well of course it is. Animals should be as well treated as a human being. Never should anyone have to be killed! When someone or something dies it should be from natural causes not from some stupid idiot who is mad at someone or something and decides to kill it!
In the eyes of the law no it is not. Nor is it in the eyes of most people. However to kill something wantonly is, perhaps, an indication of a disturbed mind.