Ken Starr has joined a list of prominent conservative attorneys to step up and rebuff Liz Cheney's recent attack campaign against Justice Department lawyers.

Cheney's political advocacy group "Keep America Safe" last week launched an ad suggesting that a number of Justice Department officials are terrorist sympathizers for having represented detainees during the Bush administration. The spot labels them the "Al-Qaeda 7" and questions their "values."

"This was very unwise, and really an out-of-bounds characterization and challenge to good, honorable lawyers," Starr said in his first-ever appearance on MSNBC's Countdown With Keith Olbermann. He called the ads "unfortunate" and "ill-conceived."

Currently the dean of Pepperdine University School of Law, Starr is best known for his investigations in the 1990s that led to the impeachment of President Bill Clinton. He has long been a target of progressives.

He defended the Justice Department attorneys targeted by Cheney, arguing that it was "in the finest traditions of our country" for attorneys to take on "unpopular causes" and defend those subjected to government power.

"You do not impute the causes of the client to the lawyer who is called upon to make sure that that client's rights are being protected," Starr said.

The former Solicitor General joins a list of conservative attorneys who have rebuked the ad campaign in a letter. Politico's Ben Smith reports:

"We consider these attacks both unjust to the individuals in question and destructive of any attempt to build lasting mechanisms for counterterrorism adjudications," wrote the 19 lawyers whose names were attached to the statement as of early Monday.

The attacks on the lawyers “undermine the Justice system more broadly,” they wrote, by “delegitimizing” any system in which accused terrorists have lawyers, whether civilian courts of military tribunals.

The letter’s signers include some of the top officials of a Bush Justice Department that wrestled at length with the legal questions surrounding terrorist detentions. []

The signers include former Deputy Attorney General Larry Thompson, John Ashcroft’s No. 2, and Peter Keisler, who served as acting attorney general during President Bush’s second term. They also include several lawyers who dealt directly with detainee policy: Matthew Waxman and Charles “Cully” Stimson, who each served as deputy assistant secretary of defense for detainee affairs; Daniel Dell’Orto, who was acting general counsel for the Department of Defense; and Bradford Berenson, a prominent Washington lawyer who worked on the issues as an associate White House counsel during President Bush’s first term.

Conservative author and attorney Paul Mirengoff, a fellow at the conservative Claremont Institute, said on Friday that the ad "could be worse than some of the assertions made by [Joe] McCarthy." Several journalists and writers have compared Liz Cheney to the notorious former Republican senator.

This video is from MSNBC's Countdown, broadcast March 8, 2010.

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