Ex-Rep. Patrick Murphy in HBO Documentary

Former Rep. Patrick Murphy, a Pennsylvania Democrat and Army veteran of Iraq who led congressional efforts to repeal "Don't Ask, Don't Tell", will appear in an HBO documentary about the history and unraveling of the anti-gay military policy.

A sneak preview of The Strange History of Don't Ask, Don't Tell is scheduled for a sneak preview at midnight tonight, with the prime-time premier at 8 p.m. Tuesday. The film is directed by Fenton Baily and Randy Barbato.

Former Rep. Patrick Murphy, Democrat of Pennsyvlania. (Getty Images.)

The title refers to the U.S. policy, established in 1993, that allowed gay people to serve in the military as long as they kept their sexual preference hidden. The policy was repealed last year, but not before more than 13,000 service members were discharged from the Army, Navy, Air Force and Marines for violating it.

"I just talked about how wrong it was, kicking out 13,000 folks who were willing to take a bullet for their country," Murphy told The Big Tent. He was interviewed twice during the legislative fight to change the policy, and then a third time at his Bucks County home last December after the fight was won.

Murphy, an Army lawyer who served in Iraq with the 82nd Airborne Division, was elected to the U.S. House from Pennsylvania's Eighth District in 2006, and was defeated in his bid for a third term last November. He is currently practicing law in Philadelphia and seekling the 2012 Democratic nomination for state attorney general.

"I thought it was wrong," Murphy said of DADT. "My mom was a Catholic nun for a little while and we were raised with a strong sense of social justice. I joined the military in 1993 and saw a lot of great folks thrown out. It's sad."

He said he admires the courage of the gay servicemen and women who stood up to challenge the policy, which was a compromise born after Congress resisted President Bill Clinton's move to lift a longstanding ban on gays in the military outright.

Murphy said he does not view his role in the change as particulary momentous: "I just did what I said I was going to do."