Actually, they aren't. Even in Texas this woman may face charges if for no other reason because she shot "through" the wall. That is a very dangerous thing to do as you don't know who is on the other side.

Also I'm not sure but I would suspect "peeping" is a misdemeanor so if true that could present a legal problem.

From a practical perspective I applaud her for eliminating the threat, real or imagined but that doesn't mean she acted in a completely legal way. We will see but they will probably no bill her.