An ethics manual prepared by the U.S. Justice Department for prosecutors in the aftermath of the botched case against Sen. Ted Stevens should remain a secret document unavailable to the public, the government told a Washington federal appeals court Thursday.

The National Association of Criminal Defense Lawyers sued for a copy of the manual, a comprehensive guide that presents case law and describes prosecution strategy in response to demands for information from the defense. The manual, formally called the Federal Criminal Discovery Blue Book, is hundreds of pages long.

A federal trial judge ruled the training manual could be shielded from the public under the attorney work-product doctrine. The criminal defense group, represented by Jones Day, appealed to the U.S. Court of Appeals for the D.C. Circuit.

“Why isn’t this quintessentially an attempt by the criminal defense lawyers and the amici to determine what the government is up to insofar as its discovery obligations, particularly in light of the Stevens case?” D.C. Circuit Judge David Sentelle asked the government’s lawyer, Lewis Yelin, in court on Thursday.

Yelin argued that the attorney work-product shield applies because the document was prepared for litigation. The criminal defense group’s lawyer, Yaakov Roth, a Jones Day associate in the Washington office, called the manual a policy document that Main Justice did not write for any specific case. “It’s the type of government policy that [the Freedom of Information Act] requires to be disclosed,” Roth told the panel judges, who included Harry Edwards and Sri Srinivasan.

Srinivasan seemed particularly interested in how to draw a line between a document specifically prepared for a case and one—like the criminal discovery manual at issue—that was designed to be used broadly as a resource before and during litigation. He noted that the Justice Department on its website publishes a Freedom of Information Act manual that provides case information about public-records suits.

“If the government had decided not to publicize that, would it be fair for the government to say that that’s attorney work-product because it tells us how we are going to litigate FOIA cases?” Srinivasan asked Yelin during one exchange. Yelin said the government could have withheld the document, yes, but that the department can always waive the work-product privilege.

Sentelle raised the possibility that the court could send the case back to the trial level to see whether any pieces of the manual could be released to the public.

The public corruption case against Stevens fell apart in 2009 amid allegations that prosecutors concealed evidence from the Alaska senator’s defense lawyers. The Justice Department heralded the manual as part of a new push to train and educate all prosecutors on their disclosure obligations.

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