"WHAT THIS is not is an indictment of our institutions, of our justice system," House Speaker Paul D. Ryan (R-Wis.) said Thursday about the now infamous "Nunes memo." "It does not impugn the Mueller investigation or the deputy attorney general," the speaker insisted. Is this cynicism or naivete?

Discrediting law enforcement is the memo's transparent purpose and why it has been embraced by President Trump. Written mainly by the staff of Devin Nunes (R-Calif.), the loose-­cannon chairman of the House Permanent Select Committee on Intelligence, the memo reportedly makes the case that the FBI abused spying authorities as it sought permission to surveil a former Trump adviser. The Justice Department called its potential release, which Mr. Trump reportedly intends to approve, "extraordinarily reckless." The FBI released its own startling public statement citing "grave concerns about material omissions of fact that fundamentally impact the memo's accuracy." Adam Schiff (Calif.), the ranking Democrat on the Intelligence Committee, wrote in a Post op-ed that the Nunes memo "cherry-picks facts, ignores others and smears the FBI and the Justice Department."

As we've said before, we are not in the business of opposing the release of information of potential public value. But if the Nunes memo were truly about fair congressional oversight of law enforcement, as Mr. Ryan claims, Republicans would allow the simultaneous release of a Democratic memo on the same subject. But they are not, though Mr. Ryan's staff says the speaker supports releasing the Democratic memo after giving it more scrutiny. That leaves only unsettling possibilities for why Mr. Nunes, a longtime Trump ally, is pushing to disseminate his version as the president's ire about the Russia investigation crests and speculation swirls about his desire to fire senior law enforcement officials, including special counsel Robert S. Mueller III and Deputy Attorney General Rod J. Rosenstein. CNN reported Thursday that Mr. Trump believes the Nunes memo "could discredit the agency" by exposing "bias within the FBI's top ranks."

The Nunes memo is either a partisan document, a distraction, or an FBI smear, according to Post opinion writers. (The Washington Post)

Mr. Ryan bears full responsibility for the deterioration of congressional oversight of intelligence operations. Once a bipartisan responsibility that lawmakers treated soberly — as they still do in the Senate — oversight under Mr. Nunes has become another front in Mr. Trump's assault on the law enforcement institutions investigating the president and his associates. House Republicans are poisoning the committee's relationship with the intelligence community and distracting from real issues demanding attention.

In all the noise around the memo, it is easy to lose sight of the scary truth that a hostile foreign government attempted to influence the 2016 election and shows every intention of trying again this year. You'd think Mr. Nunes's committee would be alarmed by this threat to American democracy. Instead, Mr. Nunes, with Mr. Ryan's aid and comfort, is helping Mr. Trump impede an investigation into these very issues. It is sad to see the speaker allow the House to be tarnished in this way.

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