Free Beer Bust Certificate, 1982
This event was most likely a fundraiser of some sort, perhaps commemorating the infamous Black Pipe incident 10 years earlier.
The Black Pipe was the former name of Duane's little bar, where in August 1972 there was a party to benefit a gay legal assistance group called HELP. The organizers were supporting a candidate for DA who was running against the incumbent. It was supposed to be a private event with pre-paid registration, but the opponent's people got wind of it. The event organizers were taking money at the door (thus letting undercover cops in), and the LAPD arrested 21.