WASHINGTON — Michael D. Cohen, President Trump’s former personal lawyer who implicated him in a scheme to pay hush money to two women claiming to have had affairs with him, said on Thursday that he had agreed to testify before a House committee next month and give “a full and credible account” of his work for Mr. Trump.
Mr. Cohen’s decision to appear before the House Oversight and Reform Committee on Feb. 7 sets the stage for a blockbuster public hearing that threatens to further damage the president’s image and could clarify the depth of his legal woes. Mr. Cohen, a consigliere to Mr. Trump when he was a real estate developer and presidential candidate as well as informally when he was president, was privy to the machinations of Mr. Trump’s inner circle and to key moments under scrutiny by both the special counsel, Robert S. Mueller III, and federal prosecutors in New York.
He could soon share many of them on national television under oath. But potential constraints emerged almost immediately on Thursday when the committee’s chairman warned that Mr. Cohen most likely would be barred by Mr. Mueller from discussing matters related to Russia.
“In furtherance of my commitment to cooperate and provide the American people with answers,” Mr. Cohen said in a statement, “I have accepted the invitation by Chairman Elijah Cummings to appear publicly on Feb. 7. I look forward to having the privilege of being afforded a platform with which to give a full and credible account of the events which have transpired.”
In August, Mr. Cohen pleaded guilty in federal court in Manhattan to tax fraud, making false statements to a bank and a campaign finance violation. In court, Mr. Cohen said that violation was the result of payments he made at the behest of his former client to a woman who was prepared to go public during the 2016 campaign about an affair with Mr. Trump years earlier.
Since then, Mr. Cohen has spent more than 70 hours with federal prosecutors in Manhattan as well as with Mr. Mueller, who is investigating Russian efforts to influence the 2016 election and Mr. Trump’s campaign. In November, Mr. Cohen pleaded guilty to an additional charge — lying to Congress about how long negotiations for a Trump Tower project in Moscow went on in 2016.
That cooperation has earned him the ire of Mr. Trump, who has called Mr. Cohen a “weak person.” The president said he did nothing wrong regarding the campaign finance charge, and he accused his former lawyer of lying to prosecutors to try to get a reduced sentence. In court filings, prosecutors have not named Mr. Trump, referring to a “candidate for federal office” and “Individual-1.”
Asked during a visit to the border in Texas whether he was concerned about Mr. Cohen’s plan to testify, Mr. Trump told reporters, “I’m not worried about it at all.”
The subjects and level of detail that Mr. Cohen will be able to go into in public remain to be seen. Mr. Cummings said he was consulting Mr. Mueller’s office to ensure that he did not hinder its efforts, and that the special counsel’s team had indicated some areas — including interactions with Russia — that would most likely be off limits.
“I want to make clear that we have no interest in inappropriately interfering with any ongoing criminal investigations,” Mr. Cummings said.
Lawmakers of both parties have sought to protect Mr. Mueller since he was appointed. That is likely to be a key theme of the Senate confirmation hearing next week for Mr. Trump’s nominee for attorney general, William P. Barr, who could soon oversee the Mueller investigation. Democratic lawmakers on the Judiciary Committee sought assurances from Mr. Barr on Thursday that he would not interfere with the investigation as it wraps up. But they left private meetings with him saying that they would need a public pledge during his hearing.
Mr. Cummings said in a brief interview on Thursday that he had known Mr. Cohen would testify for some time and had spoken with him when arranging the hearing.
“He’ll have a chance to tell his side of the story, and we’ll have a chance to question him,” he said. “The American people deserve that.”
In a CNN interview in December, Mr. Cummings compared Mr. Cohen’s appearance to that of John Dean, President Richard M. Nixon’s White House counsel, in 1973 before a special Senate committee investigating the Watergate scandal. Mr. Dean implicated himself, top administration officials and the president in a cover-up of the 1972 break-in at the Democratic National Committee headquarters.
“This is a watershed moment,” Mr. Cummings said, invoking Mr. Dean, who he said “changed the course of America” with his testimony.
It was unclear whether Mr. Cohen’s agreement to testify before the Oversight Committee would preclude appearances, in public or private, before other House panels.
The newly installed chairmen of at least two other panels have said they want to speak with Mr. Cohen about his work on behalf of Mr. Trump. Representative Adam B. Schiff, Democrat of California and the Intelligence Committee chairman, said in an interview last week that he was in touch with Mr. Cohen’s lawyer about a possible appearance.
In a statement on Thursday, Mr. Schiff said he was glad to see Mr. Cohen would appear in public, but would press ahead in trying to secure a private appearance before his own committee “in the near future” to discuss matters related to Russia. Senator Richard M. Burr, Republican of North Carolina and the chairman of the Senate Intelligence Committee, said he too had an outstanding request for Mr. Cohen to come before his investigators.
Democrats won back the House last year promising to hold Mr. Trump and his administration to account and have begun laying the groundwork for a long run of investigations targeting his administration’s policies and ethics lapses, Mr. Trump’s businesses and his campaign’s interactions with Russia. Mr. Cohen’s appearance in public, before national television cameras, will begin to fulfill that promise, but is likely to be only the first in a string of public testimony that could prove damaging to the president.
Representative Jim Jordan of Ohio, the top Republican on the Oversight Committee, was not pleased with the announcement. Democrats, he said, had wasted no time in using the committee for “political theater rather than legitimate oversight.” He also pointed out that Mr. Cohen had already “admitted to providing intentionally false and misleading testimony to Congress” once before.