House Intelligence Committee Chairman Adam Schiff has released 15 transcripts of closed-door testimony in the Democrats’ impeachment investigation, but one remains under lock and key.

It’s the transcript of the more than eight hours of testimony of Intelligence Community Inspector General Michael Atkinson on Oct. 4, noted investigative reporter Paul Sperry in a tweet.

A Republican member of the committee, Rep. John Ratcliffe of Illinois, thinks he knows why the transcript hasn’t been released.

“It’s because I asked IG Atkinson about his ‘investigation’ into the contacts between Schiff’s staff and the person who later became the whistleblower,” Ratcliffe tweeted in response to Sperry. “The transcript is classified ‘secret’ so Schiff can prevent you from seeing the answers to my questions.”

Townhall noted a committee colleague, Rep. Elise Stefanik, R-N.Y., asked Schiff a similar question at last month’s impeachment inquiry hearings and was shut down by the chairman.

“Mr. Chairman, will you be prohibiting witnesses from answering questions as you have in the closed-door depositions?” she asked.

Schiff said he would intervene only if he believed the whistleblower’s identity was about to be revealed. But the chairman has insisted he doesn’t know who the whistleblower is, a claim Republican members of the committee dismiss.

Schiff initially claimed he had had no contact with the whistleblower before receiving the complaint. However, the New York Times reported Oct. 2 that Schiff knew about “the outlines” of the whistleblower’s concerns before the Aug. 12 complaint was filed. The Times said the whistleblower had contacted an intelligence committee aide after concern about how the complaint was being handled by the CIA’s top lawyer.

Rep. Doug Collins, R-Ga., said he wants Schiff to be a fact witness in the House Judiciary Committee impeachment proceedings regarding his office’s relationship with the whistleblower.

“If he chooses not to, then I really question his veracity in what he’s putting in his report,” Collins said.

“It’s easy to hide behind a report,” Collins continued. But it’s another thing “to have to answer questions” on what he knew about the whistleblower and the report.