The Department of Justice most likely will appeal a federal judge's ruling overturning the military's gay ban, says SLDN's Aubrey Sarvis.

Sarvis, the executive director of the Servicemembers Legal Defense Network (SLDN), the nation's largest group lobbying for repeal of “Don't Ask, Don't Tell,” appeared Friday on MSNBC's Hardball.

In the segment, titled Ending 'Don't Ask, Don't Tell,' Sarvis was joined by R. Clarke Cooper, the executive director of the gay GOP group Log Cabin Republicans, which challenged the Clinton-era law that prescribes discharge for gay and lesbian service members who do not remain closeted or celibate.

On Thursday, U.S. District Judge Virginia A. Phillips ruled that the Pentagon policy violates the U.S. Constitution. The policy has a “direct and deleterious effect” on the armed services, she ruled.

Phillips said she will grant plaintiffs the injunction they seek and block the U.S. government from enforcing the law, but gave the administration one week to appeal the ruling. DOJ lawyers have only said they are reviewing the case.

But Sarvis believes the government will move against the ruling.

“I'm not going to second guess what the Justice Department is going to do, Chris, however, I think in all likelihood they probably will appeal,” Sarvis answered host Christ Matthews' question on whether the government would fight the court ruling.

Cooper agreed, saying: “I would gander that they are probably going to try to appeal it, hopefully not.”

Sarvis once again urged the Senate to join the House in repealing the policy when Congress returns to work next week.