WASHINGTON — Representative Nancy Pelosi, the Democratic leader, moved swiftly on Tuesday against the House’s longest serving lawmaker, calling for the House Ethics Committee to investigate sexual harassment charges against Representative John Conyers Jr., the top Democrat on the House Judiciary Committee.
Mr. Conyers, 88, who has represented parts of the Detroit area in the House since 1965, confirmed the settlement of a wrongful termination complaint in 2015 from a staff member who had accused him of sexual harassment. But he denied that the staff member was fired for refusing to have sex with him. The settlement was first reported by Buzzfeed News on Monday.
Ms. Pelosi and senior Democrats on the Judiciary Committee offered little support, and the Ethics Committee said it had indeed opened an investigation.
“Any credible allegation of sexual harassment must be investigated by the Ethics Committee,” Ms. Pelosi said, adding that there should be “zero tolerance for harassment, discrimination, bullying or abuse in the House.”
Sexual harassment charges are roiling Capitol Hill, as they have shaken Hollywood, Silicon Valley and the media. But in Mr. Conyers’ case, the charges quickly meshed with other issues, from the advanced age of some House members to the desire of younger Democrats for new leadership.
Specifically, the House Judiciary Committee would become a focal point for inquiries into the conduct of President Trump and his administration — possibly even impeachment proceedings — if Democrats seize control of the House in the 2018 midterm elections. And some Democrats have been angling for stronger leadership.
Mr. Conyers, who has for decades led the Democrats on the Judiciary Committee, denied any wrongdoing and said the money paid to his accuser amounted to a “reasonable severance payment.”
But legal documents published by Buzzfeed show repeated allegations by women staff members of requests for sex, suggestive touching, caresses and other sexual improprieties.
The calls for an investigation came as Democrats privately raised the prospect that Mr. Conyers would at least be asked to step aside from the coveted top Judiciary post. A founding member of the Congressional Black Caucus, Mr. Conyers holds the venerated title of Dean of the House. But he has also been a target of Democrats who are eager to bring fresh blood into the Judiciary Committee leadership for some time, three congressional officials said.
He has already handed over much of the day-to-day committee work to staff and other Democratic members in recent years, and has often appeared disoriented.
On Tuesday, some House Democrats viewed the charges as their opening to finally remove him.
“The allegations against Ranking Member Conyers are extremely serious and deeply troubling,” said Representative Jerrold Nadler of New York, the second most senior Democrat on the Judiciary Committee. “There can be no tolerance for behavior that subjects women to the kind of conduct alleged.”
A group of Democrats from across the caucus had pushed for such a move at the start of the year, but were beaten back by Mr. Conyers and allied lawmakers, according to House Democrats familiar with the matter. Since then, they said, it has been commonly understood that this term would be Mr. Conyers’s last atop the committee.
Mr. Nadler and Representative Zoe Lofgren of California have made clear to fellow Democrats that they intend to run to replace Mr. Conyers should he step aside. Following Mr. Conyers, they are the two most senior Democratic members of the committee.
“This reported behavior cannot be tolerated in the House of Representatives or anywhere else,” Ms. Lofgren said, adding that the accusations were “as serious as they get” and should be investigated expeditiously.
Speaker Paul D. Ryan of Wisconsin called the report of Mr. Conyers’s settlement “extremely troubling.”
“People who work in the House deserve and are entitled to a workplace without harassment or discrimination,” Mr. Ryan said.
However, on Tuesday morning at his home in Detroit, Mr. Conyers told The Associated Press that he knew nothing about any claims of inappropriate touching and learned of the story from television just hours earlier. “I have been looking at these things in amazement,” he told a reporter.
Hours later, a spokeswoman for Mr. Conyers hinted that the reporter’s questions confused the congressman. “Congressman Conyers was under the impression the reporter was speaking of recent allegations of which he was unaware of and denied,” the spokeswoman said.
Mr. Conyers also released a statement that began by touting himself as a “fierce advocate for equality in the workplace” and a supporter of the “rights of employees who believe they have been harassed or discriminated against.” He went on to say that though he had settled the claim, he had done nothing wrong and would “fully cooperate” if the House moved to investigate the matter.
“It is important to recognize that the mere making of an allegation does not mean it is true,” Mr. Conyers said. “In this case, I expressly and vehemently denied the allegations made against me, and continue to do so. My office resolved the allegations — with an express denial of liability — in order to save all involved from the rigors of protracted litigation. That should not be lost in the narrative.”
Mr. Conyers also pointed to the amount of money paid to his accuser — $27,111.75, according to documents obtained by Buzzfeed — in defending himself.
“The resolution was not for millions of dollars, but rather for an amount that equated to a reasonable severance payment,” Mr. Conyers said in the statement.
Debra Katz, a Washington lawyer who often works on sexual harassment cases, however said the “outrageously low” settlement amount illustrated the process’s deep flaws.
“Even with these very serious allegations, the victim of harassment received a very paltry settlement, which is typical of what happens when people even with the strongest claims come forward,” Ms. Katz.
According to the documents obtained by Buzzfeed, a former staff member said she was fired because she would not succumb to Mr. Conyers’ “sexual advances.” The publication also obtained affidavits from other staff members who said Mr. Conyers repeatedly harassed women working for him through actions that included requests for sexual acts, contacting and transporting other women with whom they believed Mr. Conyers was having affairs, caressing their hands sexually and rubbing their legs and backs in public.
Mr. Conyers found little support from fellow members of the Congressional Black Caucus or Michigan’s delegation.
Representative Debbie Dingell, Democrat of Michigan, called the allegations “deeply disturbing” and said the veteran congressman should face an investigation by the House ethics panel.
And few members of the black caucus rose in Mr. Conyers’s defense. Reached by telephone, Representative Cedric Richmond of Louisiana, the Democratic chairman of the group, said he wanted to gather more information and talk to Mr. Conyers before weighing in.
“I think it raises a bunch of questions,” Mr. Richmond said.
While the black caucus has long stood with Mr. Conyers and been among the loudest voices in defense of respecting congressional seniority, some members in the caucus are said to have little interest in continuing to back him.
Representative Karen Bass, Democrat of California, said that while Mr. Conyers had an “unbelievable” impact on history and Congress, she wanted to know more about the settlement.
“I am absolutely going to defend his legacy, but I am not going to defend sexual harassment for anyone,” she said.
At least two House Democrats said members of the caucus were hopeful that Mr. Conyers would take the hint and resign.
Ms. Pelosi also called on Congress to pass legislation that would change the way sexual harassment claims are handled.
“In addition, we must pass the Me Too Congress Act sponsored by Congresswoman Jackie Speier and enact other reforms to advance equity in all workplaces in America,” she said in a statement.