WASHINGTON — House Republicans will interview the FBI director's chief of staff today as part of a congressional probe into the agency's handling of the investigation into Hillary Clinton's use of a private email server as secretary of state.

Chief of staff Jim Rybicki will meet behind closed doors with staffers from the House Judiciary and Oversight and Government Reform committees. The panels launched an inquiry last fall into the controversy, including why former FBI Director James Comey did not recommend criminal charges against Clinton.

"You've got the person who was hopefully closest to the thinking of Director Comey, at that point his chief of staff, so hopefully he can help us understand," said Rep. Mark Meadows, R-N.C., a member of the oversight committee.

Meadows said Republicans are hoping Rybicki "can help us understand some of the thinking that went into the decisions and the memos and provide adequate justification for why decisions that seem to be incongruent with fairness and justice were made."

One key question for Rybicki will be why Comey drafted a statement exonerating Clinton months before completing the investigation in 2016, Meadows said.

"Maybe there's a logical explanation and we're hopeful to hear that," he said.

Top Senate Republicans said last fall that Comey wrote a draft conclusion for his investigation before interviewing 17 key witnesses, including Clinton.

Today's interview is the latest chapter in an investigation that Democrats charge is aimed at raising doubts about the FBI's impartiality and deflecting attention from special counsel Robert Mueller's probe into whether President Donald Trump's campaign coordinated with Russia on its meddling into the 2016 election.

Rep. Jerrold Nadler, the top Democrat on the House Judiciary Committee, who has accused Republicans of pursuing "right wing conspiracy theories from the past," declined Wednesday to comment on Rybicki's appearance. Democrats said the appearance would give Rybicki "the opportunity to rebut the negative and clearly inaccurate statements that Republicans and the president have been making about the FBI being politicized and being an institution in tatters."

Rybicki's appearance would come a day after Corey Lewandowski, Trump's former presidential campaign manager, testified behind closed doors before the House Intelligence Committee, which is investigating Russian meddling.

Former White House strategist Steve Bannon testified before the committee Tuesday, but news reports said he refused to answer a number of questions. Bannon's testimony was not public either.

The Justice Department has said it would look into whether contributions to the Clinton Foundation were linked to an Obama administration decision allowing Russia to buy a company with access to uranium in the United States.

The investigation of Clinton, the Democrats' 2016 presidential nominee, appeared to end in the middle of the election year when Comey, whom Trump fired last May, called her handling of her email careless but said "no reasonable prosecutor would bring such a case."

Comey later wrote a letter to Congress days before the election, saying the case had been reopened, followed quickly by an announcement that the case was again considered closed. Clinton has blamed her defeat in the election partly on Comey's decision to renew the investigation.

The FBI's performance is the subject of an independent investigation by the Justice Department's internal watchdog agency, which began looking into it in January 2017.

The department's Office of Inspector General has said it will review "allegations regarding certain actions" of department and FBI officials "in advance of the 2016 election."

The investigation is looking at "allegations that department or FBI policies or procedures were not followed" in connection with a Comey news conference July 5 and letters he sent to Congress on Oct. 28 and Nov. 6, 2016.

House Republicans decided last July to launch their own inquiry as Trump needled Attorney General Jeff Sessions, accusing him of being "weak" for not investigating Clinton.

The committees talked with FBI Deputy Director Andrew McCabe last month and have asked Justice for paperwork related to the Clinton investigation.

Meadows said not all the material has been delivered and he expected a "more formal and forceful response will be made in the coming days." He offered no timeline for the inquiry.

"We're at the very early stages," he said. "This could be ongoing for some time."