The basic instinct of a decent human being is to help another human being who is in distress. If you are a first responder, you are trained to do it. If you are a first responder and you don't do it, you can get into big trouble, especially since it could be caught on tape.
You can't go wrong this way, and there's time to laugh about it later in private.
As the Savior said, “I say to you, love your enemy, do good to those who hurt you, return good for evil.”
Set the example by helping him, even as you think “Serves him right”.