In the eyes of the law, a dog's owner is generally liable for injuries it causes. But every case depends on its unique circumstances and on your state's law.

The answers to a number of questions will help you get a bead on whether or not you have grounds for a lawsuit against the owner. Was the dog running loose? Did your son provoke the dog? Did the owner have reason to know the dog might hurt someone?

You should also know that you might have a claim against the school if school staff acted in a manner that was unreasonably careless and that resulted in your son's injury, or if your state's law holds property owners responsible for this kind of injury.