WASHINGTON — The former F.B.I. director James B. Comey was testifying on Wednesday before a Republican-led Senate committee seeking to discredit the investigation he opened during the 2016 election into ties between Donald J. Trump’s campaign and Russia.
With another presidential election looming, Republicans on the Senate Judiciary Committee were eager to portray President Trump as a victim of a politically motivated smear by the F.B.I. that unfairly cast a shadow over his presidency. And they will contend that Mr. Comey was the ringleader.
Mr. Comey began by strongly defending the F.B.I.’s handling of the investigation, including his decision to open it. But he was expected to acknowledge, as he has before, that his initial claims were wrong that a wiretap of a former Trump campaign adviser, Carter Page, was properly handled and concede that the bureau had been sloppy on that aspect of the broader inquiry.
He testified by video from his home.
Mr. Comey is the centerpiece of a monthslong attempt by conservatives to rewrite the Trump-Russia narrative.
Led by Senator Lindsey Graham of South Carolina, the Judiciary Committee has been pounding away for months at the F.B.I.’s investigation of ties between Russian election interference and the Trump campaign.
The panel’s work has built on an investigation by the Justice Department’s independent inspector general, Michael E. Horowitz, that found evidence of negligence and errors in one narrow aspect of the investigation: the F.B.I.’s applications to wiretap Mr. Page. But where the inspector general concluded there was no evidence of illegal activity or a politically motivated plot by senior department officials, Mr. Graham insists there may have been.
Mr. Comey signed off on some of the warrant applications and, as director, was the top bureau official responsible for the investigation until he was fired by Mr. Trump in the spring of 2017.
“The day of reckoning is upon us when it comes to Crossfire Hurricane,” Mr. Graham said in advance of the hearing, using the F.B.I. code name given to the investigation.
But in an opening statement, his focus was far more narrowly trained on the secret wiretap warrants and Mr. Graham made nary a mention of Mr. Comey.
“I’m saying this to my Democratic friends: If it happened to us, it could happen to you. Every American should be worried about this,” Mr. Graham said. “This is not just an abuse of power against Mr. Page and the Trump campaign. This is a system failure.”
Working with Mr. Trump’s Justice Department, Mr. Graham has released investigative records raising doubts about the integrity of the agents running the case and information upon which they relied, though Democrats have said they lack context and are misleading. The president, in turn, has eagerly taken the disclosures as ammunition in a long-running campaign to reshape the public’s understanding of the inquiry, which concluded the Trump campaign willingly accepted help from the Russians and that Mr. Trump sought to foil the investigation.
The committee has already publicly questioned two former deputy attorneys general, Rod J. Rosenstein and Sally Yates, who oversaw aspects of Crossfire Hurricane and signed off on the applications for the secret wiretap warrants targeting Mr. Page. Both expressed regret for errors identified by Mr. Horowitz but dismissed assertions by Republicans on the panel that their actions were politically motivated or that Mr. Trump’s campaign need not have been investigated.
Democrats have opposed Mr. Graham at every turn, accusing him of abusing his Senate powers to help Mr. Trump and take attention from the continuing Russian threat. On Wednesday, they said he was unfairly trying to discredit the entire investigation based on one small aspect of it.
“Those errors were serious, but the errors and the so-called Steele dossier — and this is important — played no part in the broader Russia investigation,” said Senator Dianne Feinstein of California, the panel’s top Democrat. She noted that of the 10 people interviewed in the committee’s investigation, not one had claimed anything different.
Mr. Comey offered a forceful defense.
Mr. Comey, who had not testified before Congress since Mr. Horowitz’s report was released in December, remained steadfast in his decision to open the investigation, arguing that the F.B.I. had sufficient reason to scrutinize the ties between the Trump campaign and Russia.
“In the main, it was done by the book, it was appropriate and it was essential that it be done,” Mr. Comey said under questioning by Mr. Graham. “Overall I am proud of the work, but there are parts of it we will talk about that are concerning.”
Mr. Comey described the problems with the wiretap as sloppy and problematic but noted that it was a small part of the larger inquiry.
“The overarching investigation was very important — the Page slice of it, far less given the scope,” Mr. Comey said.
Mr. Graham pushed Mr. Comey on whether he had been briefed on unverified intelligence made public a day earlier by John Ratcliffe, the director of national intelligence, in an apparent bid to help Mr. Trump politically. Other officials had previously rejected the intelligence, and career intelligence officials opposed disclosing it. The years-old information suggested that Russian intelligence officers had acquired information that Hillary Clinton had approved a plan to tie Mr. Trump to Russia; Mr. Comey said he did not recall being told of that intelligence.
Expect plenty of political acrimony.
Even in the best of times, Democrats and Republicans on the Judiciary Committee squabble. But after the recent death of Justice Ruth Bader Ginsburg, the committee is now on the front lines of a war over filling her seat on the Supreme Court.
Republicans are pressing ahead to try to confirm Judge Amy Coney Barrett before Election Day. Even as they prepared to publicly question Mr. Comey, Judiciary Committee aides were working overtime to prepare for nationally televised confirmation hearings in less than two weeks.
Democrats are furious and planned to use Wednesday’s hearing to protest that Republicans are rushing ahead without them. They have accused the Republicans, led by Mr. Graham, of hypocrisy for going back on statements that a president should not be allowed to fill a Supreme Court seat so close to the election.
Though Mr. Graham’s investigation into the F.B.I. long promised to bolster Mr. Trump’s re-election campaign, it has now also become tied up in Mr. Graham’s own increasingly arduous race to stay in office. The three-term South Carolinian is facing an unexpectedly strong challenge by Jaime Harrison, a Democrat who has gained traction — and millions of dollars in donations — by attacking Mr. Graham as a spineless lackey for Mr. Trump. The race is still Mr. Graham’s to lose, but he has taken to openly asking for campaign donations in Fox News appearances.