The special panel investigating the 2012 terrorist attack in Benghazi indicated Wednesday that its inquiry could continue into next year, as House Speaker John A. Boehner said the Obama administration has made it “virtually impossible” to get to the bottom of what happened.
If the panel does extend into next year, it could cause a political headache for Hillary Rodham Clinton, whose presidential campaign would be in full swing. She also has faced questions over her role in overseeing the diplomatic post that came under attack on Sept. 11, 2012, when she was secretary of state.
Mrs. Clinton may have set back the timetable even further after her attorney wrote a letter to the investigative panel saying she does not intend to meet Chairman Trey Gowdy’s request that she testify twice: once in a private transcribed interview and later in a public hearing.
Mrs. Clinton announced her bid for president last week and has dodged questions from reporters on the campaign trail about her role in deciding the levels of security at the diplomatic compound in Benghazi and the administration’s initial response in blaming the attack on an anti-Islam video rather than on terrorists.
“They could clean this up a whole lot quicker if the administration and former Secretary Clinton were in a position to actually cooperate with the committee and turn over the kind of information that we’ve been seeking for some time,” Mr. Boehner told reporters. “But the administration has made it virtually impossible to get to the facts surrounding Benghazi. And so when we have the facts, we’ll have a report.”
Mr. Gowdy has said he hopes the panel can finish its work by the end of this year. But a spokesman for the committee warned that timeline could slip with potential delays arising from factors “beyond the committee’s control.”
“Factors beyond the committee’s control, including witness availability, compliance with documents requests, the granting of security clearances and accreditations — all of which are controlled by the executive branch — could continue to impact the timing of the inquiry’s conclusion,” said panel spokesman Jamal Ware.
Mr. Gowdy wants Mrs. Clinton to testify to his committee twice.
The first appearance would be for a transcribed interview on her decision to reject a State Department-issued email address and instead set up her own server and account, which she used to conduct official business.
He then would have her testify before the committee in a public hearing to answer questions about Libya and the 2012 attack.
She has insisted she followed the rules, and said she didn’t write about classified information from that account. In a letter to Mr. Gowdy on Wednesday, her attorney, David E. Kendall, wrote that she already has publicly answered the questions about her email use.
Mr. Kendall said Mrs. Clinton is willing to attend a public hearing and that there is “no reason to delay” that appearance by first asking her to testify in private.
Her attorney has also rejected Mr. Gowdy’s request that her email server be turned over to a third-party arbiter, and said Mrs. Clinton had the server wiped clean after she turned over the emails she deemed proper.
The former secretary of state explained last month before Mr. Gowdy’s request that she used her own email server out of convenience, and said she turned over approximately 30,000 emails she deemed work-related to the State Department in December — nearly two years after she left office.
Democrats on the committee said a public hearing should be scheduled at once.
“Rather than drag out this political charade into 2016 and selectively leak portions of a closed-door interview, the committee should schedule the public hearing, make her records public, and refocus its efforts on the attacks in Benghazi,” said Rep. Elijah E. Cummings, Maryland Democrat and ranking member on the committee.
Mr. Gowdy said in a statement that more questions remain and that the committee now has thousands of pages of documents from an accountability review board about the attack that no other committee has had access to and that they expect more documents to be produced by the State Department in the days ahead.
Those documents and others, as well as interviews with witnesses who have not been questioned, will aid the committee as it prepares to invite Mrs. Clinton to appear, Mr. Gowdy said.
He said the committee plans to issue a response Thursday “setting out a reasonable path forward with respect to Secretary Clinton’s appearances to discuss both Benghazi as well as congressional efforts to ensure the public record is complete with respect to her tenure as secretary of state.”
Mrs. Clinton refused to answer questions about Benghazi when confronted Tuesday night by a reporter from the The (London) Daily Mail.
“Mrs. Clinton, when are you going to start talking to the press about Benghazi? Did you make mistakes,” the reporter asked her as she made her way through the terminal at Ronald Reagan Washington National Airport.
Mrs. Clinton ignored the question, saying nothing as she stared straight ahead and kept walking alongside her Secret Service and police escorts, according to the newspaper.
But her campaign chairman, John Podesta, issued a statement Wednesday evening saying that the 2016 time frame for the committee’s completing its work “is the most compelling evidence yet that their investigation is solely about playing politics in the 2016 presidential campaign.”
Indeed, questions about her role in the Benghazi attack and aftermath are expected to dog her throughout the campaign, and her testimony before Congress would only sharpen the nation’s focus on her answers.
“Delaying Secretary Clinton’s testimony yet again, and calling for multiple appearances by the secretary, validates the concern many of us expressed at the outset, that the committee’s true purpose was to affect the presidential race,” said Rep. Adam B. Schiff, California Democrat and a member of the committee.
But Mr. Gowdy has said the prospect of Mrs. Clinton’s candidacy will not be a factor in the committee’s work and that Mrs. Clinton has only herself to blame for the email issue.
“I didn’t tell her to get a personal server. I didn’t tell her to hire her attorney to go through these 60,000 records, and Lord knows I didn’t tell her to delete 30,000 of them,” he said last month on “Fox News Sunday.”
• S.A. Miller contributed to this report.