By Steve Tawa

PHILADELPHIA (CBS) — The senior Democrat on the House Intelligence Committee says a committee memo sent by the Republican chairman of the panel on the Trump-Russia investigation “puts the president’s political dictates ahead of the national interest.”

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Congressman Adam Schiff contends the Republican chairman of the committee, Devin Nunes, “made material changes” to the classified memo, without the knowledge of Democratic members, before it was sent to the White House.

Schiff says the decision was made for “partisan political purposes, crossing a dangerous line.”

“We don’t cherry-pick classified information, and publish it, to give the country a misleading impression to protect the president’s hide,” said Schiff.

Rep. Adam Schiff (D-CA), ranking member of the House Intelligence Committee, speaks about President Donald Trump’s State of the Union address, during an interview with Mike Allen of Axios, on Jan. 31, 2018 in Washington, D.C. (Photo by Mark Wilson/Getty Images)

During a Q&A at the University of Penn, Schiff was asked whether Nunes should step down as chairman, because the document was doctored before it went out.

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“Should he step aside? Yes,” said Schiff.

The California Democrat says it “violates the bargain made by the congress” to the FBI and Justice Department when it established intelligence committees.

“We will protect your sources and methods, and we won’t politicize what you do,” Schiff said.

Schiff suggests the end game by Republicans is to enable the White House to exert pressure to end, curtail, or cast doubt on the FBI’s Trump-Russia investigation overseen by special counsel Robert Mueller.

Committee Republicans say the memo’s release would cast light on political bias that may have affected the early stages of the probe.

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The FBI says the top-secret memo contains “material omissions of fact” that “fundamentally impact” its accuracy. President Donald Trump denies that there was any collusion with Moscow, calling it a “Democratic hoax.”