The Senate Judiciary Committee had asked in July to interview the two officials, Jim Rybicki and Carl Ghattas, and then agreed to narrow the scope of questioning after the Justice Department initially declined to make the men available.
But in a letter this week obtained by The Associated Press, the Justice Department said it would still not permit the officials to be questioned in order to "protect the integrity" of the investigation being done by special counsel Robert Mueller. Assistant Attorney General Stephen Boyd said in the letter that the overlapping areas of the committee's investigation and Mueller's probe had not yet been sorted out, or "de-conflicted."
A Judiciary Committee spokesman said Wednesday that neither the Justice Department nor the special counsel's office had "articulated any legitimate reason for why these witnesses should not cooperate with the committee's oversight."
Ghattas is the head of the FBI's national security branch and Rybicki served as chief of staff to Comey, who was fired in May by President Donald Trump. Comey has said those men were among the FBI officials with whom he shared concerns about Trump's behavior toward him, in the weeks before he was fired.
The Justice Department's refusal to make Ghattas and Rybicki available is an indication that Mueller, who is leading the Justice Department's investigation into potential ties between Russia and the Trump campaign, sees them as relevant witnesses to the events leading up to Comey's firing. Comey has said Trump asked him to end an investigation into former national security adviser Michael Flynn and had also asked him over dinner to pledge his loyalty to him.
The July 27 refusal letter from the department, which CNN was first to report, cites the department's "long-standing policy regarding the confidentiality and sensitivity of information relating to pending matters."
Sen. Chuck Grassley, an Iowa Republican and the Judiciary Committee chairman, and Sen. Dianne Feinstein of California, the panel's top Democrat, subsequently alerted the Justice Department that they would narrow the scope of the questioning. They said they did not intend to ask about the officials' work with the special counsel's office but would instead focus on "their independent recollections, as fact witnesses, of events that occurred before and including Director Comey's removal."
The Judiciary Committee is one of multiple congressional panels investigating Russian meddling in the election. The committee heard privately last week from Donald Trump Jr. about a June 2016 meeting involving a Russian lawyer and an offer to provide damaging information about his father's opponent, Hillary Clinton.
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