Cody Shearer, a political activist and former journalist, has written the report which is now being reviewed by the FBI team investigating Russian interference in the 2016 election, according to the Guardian.
Unlike former MI6 officer Christopher Steele, who compiled the first Trump-Russia dossier, Mr Shearer does not have a background in espionage. But he is said to have a large network of sources around the world as well as the financial resources to pursue leads.
While his report was initially viewed with scepticism, the FBI is still assessing its details and is “pursuing intriguing leads”, the newspaper said.
Mr Shearer, who was close to the Clinton White House in the 1990s, had shared his memo with select media organisations before the 2016 election. It was given to the FBI in October 2016, reportedly by Mr Steele after the agency requested that the ex-spy provide any documents or evidence that could be useful in its investigation.
Mr Steele told the FBI he could not vouch for the veracity of the Shearer memo, the Guardian reported, but said he was providing a copy because it corresponded with what he had separately learned during his own investigation.
The first Russia dossier by Mr Steele has become a central part of the investigations into whether the Trump campaign colluded with the Russian government. Mr Trump has insisted there was no collusion.
The man who hired Mr Steele to compile the report, Glenn Simpson of the private research firm Fusion GPS, has given 10 hours of testimony behind closed doors to the Senate Judiciary Committee.
Among other things, both dossiers allege that Mr Trump was compromised during a 2013 trip to Moscow that involved lewd acts in a five-star hotel.
The White House has denied allegations that the US president was ever compromised and has rejected claims that campaign officials ever conspired with the Russian government.
Revelations about the “Shearer memo” came as some Republican members of Congress cast doubt on the credibility of Special Counsel Robert Mueller’s Russia probe.
On Monday, Republicans on the House intelligence committee voted to release a controversial memo that reportedly alleges that senior FBI and Justice Department officials relied on questionable and politically motivated sources to justify surveillance of Mr Trump’s campaign.
Mr Trump now has five days to accept or object to the committee’s request.
According to multiple news accounts, the memo asserts that the FBI’s 2016 application for a warrant to wiretap Carter Page, a former Trump campaign adviser, was based on information in Mr Steele’s dossier.
While Republicans argue that the memo shows wrongdoing by FBI officials, Democrats say the document mischaracterises intelligence and attempts to create a narrative to show the FBI’s Russia investigation has been biased from the beginning.
The FBI did not immediately respond to The Independent's request for comment.
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