WASHINGTON — The former F.B.I. director James B. Comey testified 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 strongly defended the F.B.I.’s handling of the investigation, including his decision to open it. But he acknowledged, 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 conceded 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.
Senator Lindsey Graham of South Carolina, the Judiciary Committee chairman, renewed his criticism of the F.B.I.’s investigation of ties between Russian election interference and the Trump campaign.
The panel has for months pounded away at the inquiry, building its work 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 certifications for 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.
But in an opening statement, Mr. Graham more narrowly trained his focus on the secret wiretap warrants and 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.”
The committee has already publicly questioned two former deputy attorneys general, Rod J. Rosenstein and Sally Yates, who oversaw the Russia investigation 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, a dossier of unverified information compiled by a British former spy, Christopher Steele, that investigators relied in part on to secure court permission for the Page wiretaps.
“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 and pressed by Mr. Graham, he said he would not have signed off on the warrant applications knowing what he does now. But noted that they were a small part of the larger inquiry into links between the Trump campaign and Russia.
“The overarching investigation was very important — the Page slice of it, far less given the scope,” Mr. Comey said.
Republicans grew increasingly frustrated when Mr. Comey repeatedly said he could not remember details surrounding the investigative process, and demurred on their questions.
“With all due respect, Mr. Comey, you don’t seem to know anything about an investigation that you ran,” said an irate Senator Mike Lee, Republican of Utah.
Graham sought to focus on unverified intelligence on Russia.
As Mr. Comey defended the broader Russia investigation and played down concerns about the Page wiretap applications, Mr. Graham abruptly shifted focus to a different theory that he argued demonstrated the F.B.I.’s bias, muddying in the process the fact that American intelligence agencies concluded Russia interfered in 2016 to aid Mr. Trump.
Mr. Graham built his case around newly released unverified intelligence made public a day earlier by John Ratcliffe, the director of national intelligence, in an apparent bid to help Mr. Trump politically. The years-old intelligence, rejected by other investigators, suggested that Russian intelligence officers had acquired information that Hillary Clinton had approved a campaign plan to elevate concerns about Mr. Trump’s ties to Russia.
Pressed by Mr. Graham, Mr. Comey said he was not aware of the intelligence. Mr. Graham inaccurately insisted it was part of a pattern suggesting Democrats had helped manufacture material to justify the F.B.I.’s investigation of the Trump campaign, and then exploited that investigation for political gain.
“If you believed it would be a dereliction of duty not to look at Trump-Russia,” Mr. Graham said, then the F.B.I. should have looked at the Clinton campaign too. “There was ample evidence of the other side being involved with Russia to create a scandal around Trump.”
Mr. Comey did not agree.
“I have read Mr. Ratcliffe’s letter, which frankly I have trouble understanding,” he said.
Mr. Graham’s characterization was misleading. The F.B.I. opened its Russia investigation independently of Mr. Steele’s work, which played a role in only the Page wiretap applications, not the other parts of the sprawling inquiry, in which investigators secured more than 230 orders for communications records.
Former officials said the newly released unverified intelligence has little credibility and could have also been either Russian misinformation or merely Russian analysis of American politics.
Robert S. Mueller III, the special counsel who took over the F.B.I.’s Russia investigation, and the Republican-led Senate Intelligence Committee had both previously rejected the intelligence, and career intelligence strenuously officials were said to oppose Mr. Ratcliffe’s disclosure of it.
“I am really concerned that we are treating this Ratcliffe letter as something at all serious or credible,” said Senator Sheldon Whitehouse, Democrat of Rhode Island.
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.