The founder of Fusion GPS told the House Intelligence Committee on Tuesday that he was upset over former FBI Director James Comey’s decision to reopen the Hillary Clinton email investigation just before Election Day, a source familiar with the testimony tells The Daily Caller.

Glenn Simpson, who founded Fusion in 2011, also acknowledged to the House panel that he did not verify information in the uncorroborated and salacious dossier before briefing reporters on its contents during the campaign, the source says.

Fox News first reported similar revelations from Simpson’s seven-hour, closed-door meeting.

As part of the dossier project, which was funded by the Clinton campaign and DNC, Simpson and the dossier’s author, Christopher Steele, briefed numerous Beltway reporters about allegations in the document.

Steele has revealed in court papers in London, where he is being sued, that he was directed by Fusion to brief reporters at The New York Times, The Washington Post, CNN, Yahoo! News and The New Yorker in September 2016.

Steele gave an interview via Skype to David Corn, a reporter at Mother Jones. Corn published an Oct. 31, 2016 article that vaguely described Steele’s allegations, though without naming the retired spook.

The article was published three days after Comey sent a letter to Congress re-opening the FBI’s investigation into Clinton’s use of a private email server. Comey made the controversial decision after emails were discovered on a laptop shared by Clinton aide Huma Abedin and her husband Anthony Weiner.

Clinton and her Democratic supporters have asserted that Comey’s letter cost her the election.

Simpson’s attorney, Joshua Levy, hinted on Tuesday night that his client was not entirely certain that the dossier allegations were true when reporters were briefed on the document.

“What they did do is they contracted with Christopher Steele…this experienced British intelligence official came back with a report. That now in hindsight looks quite accurate,” Levy told reporters after Simpson’s testimony. (RELATED: Steele Says He Believes 70-90% Of Dossier Claims Are True)

Steele, a former MI6 officer, is said to have told associates that he believes that most of the dossier’s claims are true. In a book set to be published on Thursday, Guardian journalist Luke Harding reports that Steele has told associates that he believes between 70 and 90 percent of the allegations are true.

Steele has also acknowledged in court papers that at least one of the memos in his dossier required verification. He is being sued over a Dec. 13 memo he wrote that accused a Russian tech executive of using his companies to hack DNC emails.

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