Perhaps, under certain circumstances, this may be true- I'm not a lawyer. But this case looks like a friend or acquaintance gave the girls a ride to the party but didn't want to leave when they did. This happens all the time. Everyone has certain friends they'll never go to a party with- either because they always want to leave early or they stay until the host kicks them out. Again, my argument- the father should have calmed down and planned a strategy when he went to get his daughters. I mean, he had 35 miles to think about what his plan of action would be.
Imagine what would have happend if the guys had surrounded him and beat him to a pile of mush. Seems to me he knew what he was up against and prepared accordingly. He even consulted with the cops.