It makes sensational claims about years of Russian operations against President Donald Trump.
He then said Feinstein, who is seeking another term, "Must have tough Primary!"
Feinstein said Wednesday that with the transcript's release, "people can make up their own minds" about what materialized during the committee's interview with Simpson, noting that she meant to apologize to Grassley for not notifying him first. But Billionaire activist Tom Steyer, long rumored to be pondering a bid, will not get in the race - according to the L.A. Times. But his investigation has already resulted in Trump's former national security adviser, Michael Flynn, pleading guilty to lying to the FBI about conversations with Russia's ambassador. And on Tuesday, the public was given a glimpse, in the release of secret testimony, into the fierce battle between Senate Democrats and Republicans over the dossier and how the F.B.I. made use of it during the 2016 campaign.
Investigative journalist Bob Woodward, who has written about the intelligence community for four decades, said shortly after the dossier's publication that Mr. Steele had produced a "garbage document".
A released Senate transcript shows dossier paymaster Glenn Simpson had pure praise for the work of dossier writer Christopher Steele - an assessment disputed by intelligence professionals who have studied the product.More news: Mark Wahlberg was paid $1.5M to Michelle Williams' $800
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Several important questions, however, remain unanswered, and Simpson, Fusion GPS and Steele are not fully inoculated against some of the charges they've endured from allies of the White House and other critics.
Speaking aboard Air Force One in July, Trump used the phrase "witch hunt" several times, declaring ongoing questions about Russian Federation to be a politically motivated "witch hunt" overplayed by the press.
Feinstein, under a wave of criticism for the move, said Tuesday she wanted to release the testimony to "set the record straight". Right now, a new Quinnipiac poll has his approval rating at 36 per cent and a majority of the public distrusts him. In fact, Steele was so shocked by what he learned from his sources that he felt obliged to report it to the FBI, Simpson says.
Comey briefed Trump on the existence of the file during the presidential transition, as well as the fact that US intelligence believed it might appear in the press. It's worth noting here that Feinstein says that Grassley didn't consult with her before referring Steele for investigation.
Feinstein also took advantage of a televised meeting with the President and leading Republicans and Democrats on immigration.