Republicans leading Russia probe ignored every lesson I learned as a prosecutor: Adam Schiff The House GOP ignored best practices in its investigation of Russian interference. As a former prosecutor of complex crimes, let me count the ways.

Adam Schiff | USA TODAY

Show Caption Hide Caption Dems: "Significant evidence" of Trump collusion Democrats on the House intelligence committee are sharply disagreeing with Republicans on the panel who say they don't see any evidence of collusion or coordination between President Donald Trump's 2016 campaign and Russia. (March 13)

Almost 30 years ago, as a young assistant U.S. attorney, I prosecuted an FBI agent for providing classified information to the Russians. Little did I know that my experience as a prosecutor would be so relevant to my current duties in Congress. It wasn’t just what I learned about Russian tradecraft. Far more important, my experience taught me a great deal about how to investigate complex crimes.

Investigations have a certain rhythm: You begin with solid leads, use subpoenas to compel testimony or documents from reticent witnesses, interview lower-level witnesses first and then move on to higher-level targets. Republicans on the House Intelligence Committee did none of these things before shutting down their Russia investigation last week.

Instead, they announced they would write a report to exonerate the president and even contest the Intelligence Community’s unanimous conclusion that Russia sought to help Donald Trump. Their initial commitment to “follow the facts” is now the latest casualty of the political imperative of protecting the president, no matter the cost to our democracy. With this week’s attacks on special counsel Robert Mueller, the only question is whether his investigation will be next.

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If the committee Republicans intended to conduct a serious investigation, the path was obvious. They would have interviewed key witnesses like George Papadopoulos, Michael Flynn, KT McFarland and scores of others, and compelled answers from those we did interview but who refused to answer our questions.

Instead, they uniformly refused Democratic requests to subpoena travel, bank, calendar, phone and Twitter Direct Message records. Witness interviews were rushed and scheduled haphazardly with no apparent order. Often the most important witnesses were brought in first (like Jared Kushner), and frequently before witnesses provided documents we needed to inform our questions.

During interviews, Republican lawmakers followed a familiar pattern. They would ask each witness the “three C’s” as they became known: “Did you collude, conspire, or coordinate with Russia?” If a witness answered “no,” all too often that was the end of the matter for Republicans. It’s like asking the getaway driver if he robbed the bank and accepting “no” for an answer, rather than asking why he owned the car used in the heist, why his alibi didn’t check out, or why marked bills were found in his house.

The fundamental un-seriousness of the Republican majority was most glaring when witnesses simply refused to answer, asserting non-existent, overly broad or farcical claims of privilege, or giving no basis at all. In permitting witnesses to choose their questions, the majority made a serious investigation impossible, and hobbled future congressional oversight by setting a terrible precedent.

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Attorney General Jeff Sessions was allowed to refuse to answer whether he was instructed by the president to take an action that might constitute obstruction of justice. Don Jr. could claim attorney-client privilege to stop questions about his father’s role in the false statement about the Trump Tower meeting with Russians attended by Don Jr. and other campaign aides. Hope Hicks refused to answer the same, and Corey Lewandowski would not answer any questions that he, well, didn’t want to, or didn’t meet his standard of pertinence. In each case, Republicans said nothing, or worse, intervened to support the stonewalling.

The closest they came to insisting on answers was with Steve Bannon, and only then because Bannon was out of favor with the White House and Breitbart. When he refused to discuss anything after the campaign, Republicans did issue him a subpoena. But when he came back and refused to answer anything beyond a list of 24 questions “helpfully” prepared for him by the White House (and even then, his answer to each was a simple “no”), our Republican majority again backed down. And they haven’t said a word since.

At the outset of our investigation, I said that the most profound public service we could offer would be a joint report to the American people. Republican efforts to protect the president at the cost of a serious investigation would make that impossible. The next best thing will be to release the entire body of witness transcripts, so the public can see the facts for themselves. Republicans publicly committed to doing so, and we will hold them to it. If they resist, the public will know that the record does not support their conclusions, and that the transcripts will reveal the shallow depth of their efforts.

Rep. Adam Schiff, D-Calif., is the senior Democrat on the House Permanent Select Committee on Intelligence. Follow him on Twitter: @RepAdamSchiff