The Penguin intentionally hits Batman with his umbrella. Batman, stunned by the blow, falls backward, knocking Robin down. Robin’s leg is broken in the fall, and he cries out, “Holy broken bat bones!...

The Penguin intentionally hits Batman with his umbrella. Batman, stunned by the blow, falls backward, knocking Robin down. Robin’s leg is broken in the fall, and he cries out, “Holy broken bat bones! My leg is broken.” Who, if anyone, has liability to Robin? Why?