Whose fault is it?

A black and tan dog stands on a dirt path in front of a building, facing a group of young men sitting on a low concrete step. One man in a striped shirt holds a metal bowl, and as a man in a red shirt steps out of the doorway carrying a bowl, the dog lunges forward, causing the man in the striped shirt to fall backward. The man in the red shirt stumbles and falls into the doorway, and the man in the striped shirt scrambles to his feet, still holding his bowl, as the others react to the commotion.