Speaker Nancy Pelosi on Tuesday after the State of the Union address at the Capitol.Tom Brenner for The New York Times
WASHINGTON — The House Intelligence Committee on Wednesday began a broad inquiry into whether Russia and other foreign powers may be exercising influence over President Trump, acting only hours after a defiant Speaker Nancy Pelosi declared that the House would not be cowed by the president’s “all-out threat” to drop its investigations of his administration.
Other committees were zeroing in on similarly sensitive oversight targets. On Thursday, Democrats will begin their quest to secure the president’s long-suppressed tax returns. The chairman of the Judiciary Committee readied a subpoena for the acting attorney general, Matthew G. Whitaker, in case he tried to avoid Democratic questioning. And a House Appropriations subcommittee chairwoman began an inquiry into administration rule-bending during the 35-day partial government shutdown.
“It’s our congressional responsibility, and if we didn’t do it, we would be delinquent in that,” Ms. Pelosi said of the House’s oversight role, hours after Mr. Trump used his State of the Union address to warn that “ridiculous partisan investigations” threatened the nation’s economic health and the prospects of bipartisan legislating.
That, Ms. Pelosi said, “was a threat — it was an all-out threat.”
The confrontation between a newly empowered House majority and a president of the opposite party drew comparisons to Democrats’ investigations of the George W. Bush administration after the 2006 elections and Republicans’ blitz of Barack Obama’s administration after the 2010 midterms. But Democrats and even some Republicans conceded that the targets offered up by Mr. Trump and his administration were far more numerous than his predecessors’, and his threats and protests have been more vocal.
House and Senate negotiators are rushing to reach agreement on a border-security funding bill before the government again runs out of money at midnight Feb. 15, so Mr. Trump’s suggestion that bipartisan legislating will be impossible amid Democratic investigations could hold weight.
But despite that warning, the gears of congressional oversight — which were mostly still under Republican control during Mr. Trump’s first two years in office — began to pick up speed on Wednesday in the portrait-lined hearing rooms of the House office buildings.
Meeting for the first time this Congress, the Intelligence Committee laid out a five-point investigation of the president’s potential foreign entanglements that was far broader in scope than previously expected.
Democrats said they had reopened the inquiry into Russia’s election interference efforts and possible collusion with the Trump campaign that the Republican majority closed last year. But they will layer on “interconnected lines of inquiry,” including whether Russia or other foreign actors hold financial or other leverage over Mr. Trump and his associates that at any point could have influenced American policy. Democrats also added a broadly construed obstruction of justice component to their work for the first time.
Mr. Trump dismissed the inquiry after it was announced, targeting the Intelligence Committee chairman, Adam B. Schiff of California.
“He’s just a political hack. He’s trying to build a name for himself,” Mr. Trump said, adding, “It’s called presidential harassment. And it’s unfortunate. And it really does hurt our country.”
Mr. Schiff shot back, “I can understand why the idea of meaningful oversight terrifies the president. Look, several associates of his have gone to jail. Others are awaiting trial.”
He said the expanded Russia investigation would be done in coordination with other committees, including the Financial Services Committee, which wants to determine whether Russia or other foreign actors laundered money through the Trump Organization.
“Our job involves making sure the policy of the United States is being driven by the national interest,” Mr. Schiff said, “not by any financial entanglement, financial leverage or other form of compromise.”
Intelligence Committee Republicans, who have already begun to accuse the Democrats of politically motivated overreach, did not endorse the inquiry’s parameters. In a separate statement, they called on Democrats to subpoena unnamed witnesses they recommended, and privately, they accused Democrats of being more interested in keeping a politically damaging issue alive for the 2020 elections than finding new facts.
In its meeting, the committee also voted to share transcripts of witness interviews that it conducted related to Russian election interference with the special counsel, Robert S. Mueller III. Mr. Mueller has already used two such transcripts to charge associates of the president’s with lying to Congress, and Democrats believe others could have intentionally misled the committee.
Other committees were making moves, too.
The Judiciary Committee had called a meeting for Thursday to vote on a subpoena to compel testimony from Mr. Whitaker, if needed. Mr. Whitaker, a loyalist of the president’s who is currently overseeing Mr. Mueller’s work, is scheduled to testify voluntarily on Friday, but Democrats have concerns that he might try to back out or dodge questions about the firing of his predecessor, about the president’s attacks on the Justice Department and about other matters related to the Mueller inquiry.
“For the first two years of the Trump administration, Congress allowed government witnesses to dodge uncomfortable questions,” the committee’s chairman, Representative Jerrold Nadler of New York, wrote in a statement. “That era is over.”
Perhaps most personally for the president, a Ways and Means oversight subcommittee will hold its first hearing on Thursday to start building a public rationale to pursue Mr. Trump’s tax returns.
An obscure provision in the federal tax code gives the chairman of the committee unilateral powers to request from the Treasury Department tax information on any filer, including the president.
Democrats view obtaining Mr. Trump’s returns — which he has refused to release, defying modern political norms — as necessary for their broader inquiries into potential conflicts of interest between his role as president and his business operations, as well as accusations of money laundering that may have involved Russian oligarchs or other financial crimes. But the request is fraught with tension, both because of an anticipated legal challenge from the administration and because of pressure from the party’s left flank on leaders who are proceeding slowly to try to build an airtight public relations and legal case first.
Meantime, Representative Betty McCollum of Minnesota, the chairwoman of the Appropriations subcommittee that funds the Interior Department, asked the Government Accountability Office to issue a formal opinion on the administration’s diversion of user fees at the national parks to fund operations during the government shutdown. Such funds are supposed to be earmarked for long-term capital improvement projects.
And Democrats on the Oversight and Reform Committee took their own swipe at the president at a hearing examining proposed ethics rules for the executive branch.
“Both Democratic and Republican ethics experts warned President Trump to do this years ago, but he refused,” said Representative Elijah E. Cummings of Maryland, the chairman of the committee. “They warned that every decision he made could be questioned, and the American people would rightly wonder whether he was serving the nation’s interests or his own financial interests. Unfortunately, that is exactly what has happened over the past two years.”
Advisers around the president have been preparing for the congressional onslaught for months, and they know there is little hope of dissuading Democrats, who won control of the House by promising to be a check on Mr. Trump. That, and the long history of congressional oversight of the executive branch, made Mr. Trump’s comments on Tuesday night all the more surprising to lawmakers.
“An economic miracle is taking place in the United States — and the only thing that can stop it are foolish wars, politics or ridiculous partisan investigations,” the president said amid a broader call for bipartisan cooperation. “If there is going to be peace and legislation, there cannot be war and investigation. It just doesn’t work that way!”
Ms. Pelosi called that a false choice, telling reporters on Wednesday that Democrats could engage with Mr. Trump on issues like immigration and reducing prescription drug pricing while also holding his administration accountable.
While the president’s strongest allies on Capitol Hill sought to train attention on Democrats’ aggressive maneuvering, other Republicans shrugged off Mr. Trump’s comments.
“The president has a habit of expressing what he is feeling, and he expresses himself often,” said Senator Lamar Alexander, Republican of Tennessee. “But he also enjoys going to bill signing ceremonies, like the one we had for criminal justice reform. We are used to politics around here, and conflict, and the president can express himself, but we are going to continue to work on a bipartisan basis to get things done.”
Earlier, in a closed-door meeting with House Democrats, the speaker had privately criticized the president over his State of the Union address.
“He was a guest in our House chamber, and we treated him with more respect than he treated us,” she told fellow lawmakers, according to a Democratic aide in the room who was not authorized to discuss the private session publicly.
Ms. Pelosi also took a dig at Mr. Trump’s plan, detailed on Tuesday, to invest $500 million over 10 years toward the development of new cures for childhood cancer, characterizing it as paltry.
“Five hundred million dollars over 10 years — are you kidding me?” she said, according to the aide. “Who gave him that figure? It’s like the cost of his protection of his Mar-a-Lago or something.”