WASHINGTON — House Democrats are scrutinizing whether President Trump has improperly interfered at the Justice Department for political reasons, a prominent committee chairman said Friday, requesting documents and interviews with more than a dozen U.S. attorneys related to the cases of three Trump associates and a review of the F.B.I.’s Russia inquiry.
The requests are the first major return to politically charged oversight matters by the House Judiciary Committee since it helped impeach Mr. Trump late last year. But with House leaders intent on shifting attention toward domestic policy legislation they believe will help preserve their majority in this fall’s election, it was not clear how far Democrats would be willing to escalate a likely fight.
Officials were careful on Friday not to characterize the requests as the beginning of a new investigation, instead framing them as routine oversight. They come as Mr. Trump has moved aggressively in the wake of his impeachment acquittal to insert himself into Justice Department business.
“These circumstances are deeply troubling,” Representative Jerrold Nadler, Democrat of New York and the Judiciary Committee chairman, wrote in a letter to William P. Barr, the attorney general. “Although you serve at the president’s pleasure, you are also charged with the impartial administration of our laws. In turn, the House Judiciary Committee is charged with holding you to that responsibility.”
Mr. Nadler asked for materials related to a handful of criminal cases, including the sentencing of Roger J. Stone Jr., antitrust matters and a review by John H. Durham into the roots of Robert S. Mueller III’s investigation into 2016 Russian election interference and the Trump campaign. Democrats believe Mr. Durham’s inquiry is designed to undermine Mr. Mueller’s findings.
In most of the cases under scrutiny, Mr. Trump has blurred the lines that traditionally separate the White House from criminal enforcement matters, offering running commentary or outright rooting for a result on Twitter and in public comments. Documentary records and interviews with prosecutors could definitively show whether the department acted based on Mr. Trump’s statements or if the White House at any point issued more direct orders in private.
In the case of Mr. Stone, the president’s remarks on Twitter blasting the judge and Justice Department lawyers for recommending too harsh a sentence for his longtime friend and campaign adviser went so far that Mr. Barr delivered an extraordinary public rebuke, but only after senior department officials intervened to reverse the recommendation of career prosecutors and suggest a shorter sentence.
The attorney general said earlier this month that he would not be “bullied” into any result and warned that the president’s tweets made it “impossible for me to do my job and to assure the courts and the prosecutors in the department that we’re doing our work with integrity.”
Though tensions have eased somewhat in recent weeks, Mr. Barr remains in a precarious position. Mr. Trump has largely defied his request, continuing to tweet about the Stone case and forcing Mr. Barr to contemplate what it would take for him to resign. The Judiciary Committee’s scrutiny could only make things more difficult for the attorney general, whose actions have drawn intense criticism inside and outside the Justice Department for politicizing the law enforcement system.
Mr. Nadler cited those tensions as he asked for the materials by mid-March so the committee could study the matter before a planned hearing with Mr. Barr on March 31.
If history is any guide, though, the exchange will not be an easy one. The department generally opposes handing over files related to ongoing matters, especially to lawmakers of another party, though it has made exceptions. And Mr. Nadler and Mr. Barr have particularly bad blood, stemming from the attorney general’s handling of the special counsel’s investigation. In a dispute over department files related to that case, the Judiciary Committee ultimately recommended holding Mr. Barr in contempt of Congress.
In addition to the Stone case and the Durham review, the committee requested information on the department’s handling of prosecution of Michael T. Flynn, Mr. Trump’s former national security adviser, and the imprisonment of Paul Manafort, his one-time campaign chairman. Mr. Nadler also said he would review the Justice Department’s legal opinion that an anonymous whistle-blower complaint related to Ukraine that ultimately helped prompt the impeachment inquiry not be handed over to Congress.
Specifically, the committee asked for the department to brief lawmakers on each case, hand over any communications with or referencing Mr. Trump or the White House related to them, and allow more than a dozen department prosecutors to sit for interviews.
The prosecutors requested included Mr. Durham; four career prosecutors who resigned from the Stone case amid the sentencing dispute with politically appointed superiors; and Timothy Shea, the acting U.S. attorney who oversaw them.
Democrats also want to speak to two high-ranking prosecutors from the Southern District of New York and Jessie K. Liu, a former department prosecutor, who handled the case of Andrew G. McCabe, a former high-ranking F.B.I. official loathed by Mr. Trump.
Katie Benner contributed reporting.