WASHINGTON — Chad Wolf, the acting secretary of homeland security, told senators at his confirmation hearing on Wednesday that white supremacist extremists represented a lethal domestic terrorist threat, even as he strongly denied suppressing a report that would have rendered that judgment more officially.
“It’s a fabrication, completely,” Mr. Wolf said of charges that he buried a Homeland Security Department threat assessment that singled out racist extremists, as well as Russian election interference, because it would have reflected poorly upon President Trump.
Mr. Wolf, who has emerged as one of Mr. Trump’s most loyal cabinet members, was pressed over how the agency had responded to unrest, election interference and domestic terrorism during a hearing that could propel him to become the first confirmed head of the department in more than a year.
Mr. Wolf’s confirmation hearing before the Senate Homeland Security and Governmental Affairs Committee, lasting just under two hours, came amid allegations from current and former members of his department that the agency had mishandled or downplayed the rising threats of Russian interference and violent white supremacy. The timing of the hearing, about 10 months after Mr. Wolf was tapped to lead the agency on an acting basis, was emblematic of the carousel of leadership at a department that has been riddled with vacancies throughout the Trump administration.
Even the legitimacy of Mr. Wolf’s acting position was cast into doubt last month when the Government Accountability Office issued a report saying his appointment was illegal, a finding Mr. Wolf disregarded on Wednesday as “nonbinding.”
“Vacancies and acting officials are a part of every administration, but they should be rare,” said Senator Gary Peters of Michigan, the top Democrat on the committee. “This administration has abused vacancies to the detriment of this department.” He added that Mr. Wolf “has been involved in some of the most controversial and concerning decisions the department has made.”
Mr. Wolf faced questions over allegations made by the department’s former intelligence chief, Brian Murphy. Mr. Murphy claimed that the acting secretary and his deputy, Kenneth T. Cuccinelli, directed him to hold back reports that warned of white supremacist extremism and Russian attempts to denigrate the mental health of Joseph R. Biden Jr., the Democratic nominee for president, because of how they would “reflect upon President Trump.”
Mr. Wolf repeated his defense that he did not withhold the intelligence bulletin about Mr. Biden in July because of its contents, but because he wanted the presentation of the findings improved. A copy of the September version of the bulletin obtained by The New York Times showed the report grew by only about two pages and still detailed the efforts by Russia to interfere in the election and target Mr. Biden.
Mr. Peters pressed Mr. Wolf on how such minor revisions could have taken around two months and why Mr. Wolf asked to review this specific item from an intelligence office that issues such reports regularly.
“I think the important part is the underlying intelligence did not change. I didn’t direct them to change it,” Mr. Wolf said. “I was focused on the quality of the product itself.”
Mr. Wolf also echoed comments made by Christopher A. Wray, the F.B.I. director, during a House hearing last week about the rising threat of violent white nationalists.
“White supremacist extremists, from a lethality standpoint over the last two years, particularly when you look at 2018 and 2019, are certainly the most persistent and lethal threat when we talk about domestic violent extremists,” Mr. Wolf said.
But he said the most deadly threats to the United States overall are foreign adversaries, pandemics and national disasters. He also said the government “cannot ignore” anti-government groups, such as antifa, a leaderless coalition of people who oppose fascism but have at times used vandalism and violence to make their points.
Mr. Murphy had also said Mr. Wolf retaliated against him when Mr. Murphy protested the blocking of the assessments, a claim Mr. Wolf denied on Wednesday.
“I reject any claim that I attempted to influence or retaliate against any individual at D.H.S., but specifically Mr. Murphy,” he said.
The House Intelligence Committee and the Department of Homeland Security’s Office of Inspector General are investigating the assertions by Mr. Murphy, who is still an employee with the agency. Mr. Wolf demoted Mr. Murphy after it emerged that his office had included the tweets of American journalists in intelligence briefings distributed to law enforcement agencies, a step seen as a potential infringement on First Amendment rights.
Mark S. Zaid, Mr. Murphy’s lawyer, said he and his client “outright challenge Mr. Wolf’s testimony.”
“We look forward to the opportunity to provide classified testimony to congressional and O.I.G. oversight authorities to describe details to the contrary,” Mr. Zaid said.
Former Homeland Security Department officials, including a former top terrorism official, Elizabeth Neumann, and chief of staff, Miles Taylor, have concurred that the administration downplayed threats of domestic terrorism and election interference.
Republicans used the hearing to portray Mr. Wolf as a seasoned government official who has used his experience in various branches of the department to respond to multiple national emergencies, including the coronavirus pandemic, national disasters and border crossings.
Mr. Wolf, who joined the department at its creation as a member of the Transportation Security Administration, was hailed by Senator Ted Cruz, Republican of Texas, for his response to demonstrations in Portland, Ore.
“Mr. Wolf took his responsibility to protect federal facilities and protect federal personnel with the greatest seriousness,” Mr. Cruz said.
The inspectors general of the Justice and Homeland Security Departments are investigating the methods of the camouflaged tactical agents deployed to the city, including videos that captured officers spraying tear gas indiscriminately and forcing protesters into unmarked vans. The teams were deployed despite objections from local officials, a move that prompted condemnation from former senior Homeland Security Department officials.
Mr. Wolf said 125 federal officers got temporary eye injuries after they were targeted by people in the crowds with lasers.
Senator Ron Johnson of Wisconsin, the chairman of the committee, allowed Mr. Wolf to respond to multiple allegations, including an NBC News report that the firm where Mr. Wolf’s wife works received $6 million in contracts from the department since 2018, the same year Mr. Wolf became chief of staff for the homeland security secretary at the time, Kirstjen Nielsen.
“I have no role in procurements,” Mr. Wolf, a former lobbyist, said in response to the findings. “I don’t even see procurements until they are released and on the street.”
Mr. Wolf said if he were involved in procurements, he would recuse himself from any deal with his wife’s firm or his former clients.
Mr. Wolf said officials from the inspector general’s office were speaking to employees at a privately run detention facility, where a whistle-blowing nurse claimed immigrant women underwent gynecological procedures without fully understanding or consenting to them.
The nurse, Dawn Wooten, has said in a formal complaint that several women detained at Irwin County Detention Center in Georgia told her they were given hysterectomies without their consent. The lawyer for the hospital where the procedures are said to have occurred said records show that just two women in immigration custody were referred for the surgery at the hospital since 2017.
“Some of the facts on the ground and facts we have seen do not back up those allegations,” Mr. Wolf. “But if there is a kernel of truth to any of that, you can guarantee I’ll hold those accountable and we’ll take decisive action.”