The operative words here are could have been - nobody was injured or killed. Of course, if that did happen, then the usual consequences of injuring or killing someone with a firearm ensue. The problem is, there are many things that could injure someone, and you cannot simply make them all illegal, otherwise driving would be an offence. However, note that negligence is probably citeable as a factor in some of these cases, so perhaps that is the route to go down?
To me, this sounds completely crazy. If a person was standing by the door or window they could have been injured or killed!