“Within our committee, we certainly have a compelling interest in making sure that U.S. policy … is not driven by leverage that the Russians have over the president,” Schiff told me. “There have been credible allegations that the Russians may have laundered money through the Trump organization, and if that’s the case, then we need to be able to look into it and be able to tell the country, ‘Yes, this is true,’ or ‘No, this is not.’ But I think it would be negligent not to find out.” (“I keep hearing things about investigations,” Trump observed during a press conference on Wednesday. “They got nothing, zero. You know why? ’Cause there is nothing.”)

Schiff noted that Deutsche Bank, which was recently fined for failing to prevent Russian money laundering, loaned Trump money when other banks wouldn’t; that Donald Trump Jr. once spoke of money pouring into the Trump Organization from Russia; and that the president sold a Florida mansion to a Russian oligarch in 2008 for more than twice what he had paid for it only several years earlier.

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The congressman declined to detail the next steps of a possible investigation into Russia’s interference in the 2016 election, but indicated that he sees the work as correcting the failures of the House Intelligence Committee’s earlier Republican-led probe. That inquiry existed alongside investigations by Mueller and the Senate Intelligence Committee, and petered out last spring amid partisan acrimony.

Schiff offered one example of a theory about the president that he would seek to verify: Whether or not Trump was on the other end of a call that Donald Trump Jr. placed to a blocked number in June 2016. That call happened while his son was in the midst of arranging a meeting with Russians affiliated with the Kremlin who were peddling damaging information about Hillary Clinton, a detail that Democrats first flagged last spring as a point for further inquiry.

“We know the president used a blocked cellphone during the campaign, and so naturally we sought to subpoena the phone records to determine whether the president, despite his protestations to the contrary, was knowing and approving of this meeting with the Russians to get dirt on his opponent,” Schiff said, without elaborating on the source of the claim that Trump frequently used a blocked number. “The Republicans refused. They said, ‘We don't want to know.’ And that's the attitude they have taken during their role in the investigation.”

The White House did not immediately respond to a request for comment on whether Trump used a blocked number during the campaign, or on the other allegations and concerns Schiff mentioned.

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The scrutiny from a Schiff-led committee and others may intensify the Russia probe. But he plans to dig even deeper.