Issue---the dog

Recently, I hear a news about the wandering dog. This event occurs in a university. There are many dogs around the school. One day, a French teacher who was riding the bicycle in the school. A wandering dog was running after him. The French teacher was very scared, so he rode the bicycle faster. He was too nervous, so he fell down from the bicycle. Unfortunately, he bumped his head. Now, he is in a coma. Who has to take this responsibility? Is the school or the wandering dog? If I am the judge, I do not know how to do…