By John Solomon

Opinion Contributor

Just weeks after the FBI opened a dramatic counterintelligence probe into President Trump Donald John TrumpFederal prosecutor speaks out, says Barr 'has brought shame' on Justice Dept. Former Pence aide: White House staffers discussed Trump refusing to leave office Progressive group buys domain name of Trump's No. 1 Supreme Court pick MORE and Russia, one of his presidential campaign advisers emphatically told an undercover bureau source there was no election collusion occurring because such activity would be treasonous.

George PapadopoulosGeorge Demetrios PapadopoulosTale of two FBI cases: Clinton got warned, Trump got investigated Trump says he would consider pardons for those implicated in Mueller investigation New FBI document confirms the Trump campaign was investigated without justification MORE says his spontaneous admission to London-based professor Stefan Halper occurred in mid-September 2016 — well before FBI agents and the Obama Justice Department sought a Foreign Intelligence Surveillance Act (FISA) warrant to collect Trump campaign communications in the final days before the election.

“He was there to probe me on the behest of somebody else,” Papadopoulos told me in an interview this week, recalling the Halper meeting. “He said something along the lines of, ‘Oh, it’s great that Russia is helping you and your campaign, right George?’ ”

Papadopoulos said Halper also suggested the Trump campaign was involved in the hacking and release of Hillary Clinton Hillary Diane Rodham ClintonBloomberg rolls out M ad buy to boost Biden in Florida Hillicon Valley: Productivity, fatigue, cybersecurity emerge as top concerns amid pandemic | Facebook critics launch alternative oversight board | Google to temporarily bar election ads after polls close Trump pledges to make Juneteenth a federal holiday, designate KKK a terrorist group in pitch to Black voters MORE’s emails that summer. “I think I told him something along the lines of, ‘I have no idea what the hell you are talking about. What you are talking about is treason. And I have nothing to do with that, so stop bothering me about it,’ ” Papadopoulos recalled.

The former campaign aide is set to testify behind closed doors Thursday before two House panels.

Sources who saw the FISA warrant and its three renewals tell me there is no mention of Papadopoulos’s denial, an omission of exculpatory evidence that GOP critics in Congress are likely to cite as having misled the court.

A source directly familiar with the Russia probe declined to discuss specifics of the Papadopoulos-Halper conversations but acknowledged the FBI possessed one or more transcripts that called into question the Trump campaign’s — and specifically Papadopoulos’s — alleged complicity with Russia.

The FBI officially opened the Trump-Russia case on July 31, 2016, based on suspicions that Papadopoulos had prior knowledge that Russia hacked Clinton’s emails, but it quickly pivoted by early fall 2016 to evidence such as the Democratic-funded dossier produced by Christopher Steele, and Trump campaign adviser Carter Page’s trips to Moscow. The FISA warrant was drafted to target surveillance at Page but also cited Papadopoulos in a section that suggested Russia was coordinating election collusion through Page and "perhaps other individuals associated" with Trump's campaign.

“The truth is, the Papadopoulos predicate went into reversal, but rather than shut down the probe at that point, the bureau turned to other leads like Steele and Page without giving the court a full picture,” one source said.

Some in Congress are bracing for the possibility that Deputy Attorney General Rod Rosenstein Rod RosensteinDOJ kept investigators from completing probe of Trump ties to Russia: report Five takeaways from final Senate Intel Russia report FBI officials hid copies of Russia probe documents fearing Trump interference: book MORE might argue in his interview with lawmakers that the FBI did not have an obligation to disclose all exculpatory evidence to the FISA judges. Such an argument is contrary to how the court works, according to officials who prepare FISA warrants. The FBI is required to submit only verified information and to alert the court to any omissions of material fact that cast doubt on the supporting evidence, including any denials, these officials told me.

Papadopoulos said his discussions with Halper — identified this year by The Washington Post as an FBI informant in the Russia case — were among more than a half-dozen contacts that U.S. and Western intelligence figures initiated with Papadopoulos during the campaign.

Other contacts were initiated by Defense Intelligence Agency (DIA) officials, an Australian intelligence agent, an Australian diplomat, an Israeli diplomat and British diplomats, Papadopoulos told me. At least one contact sought to offer him sex in return for information, he alleged.

Nearly all the contacts occurred in London, between April and October 2016, while Papadopoulos served as a foreign policy adviser to the Trump campaign, and after a different London professor, Joseph Mifsud, had told Papadopoulos the Russians planned to release thousands of emails from Clinton they possessed, Papadopoulos said.

Papadopoulos said he never asked Mifsud for the emails and did not act on his tip, though he told a few people about Mifsud’s claim. Papadopoulos eventually pleaded guilty to lying to the FBI about the timing and content of his conversations with Mifsud; he was sentenced to 14 days in jail.

Once Mifsud conveyed the information to him, Papadopoulos began getting overtures from Western and U.S. intelligence.

In late April 2016, for example, two officials at the U.S. Embassy in London, who identified themselves as DIA officers, probed Papadopoulos for information about Trump and Russia.

“They were wining and dining me as if I were Marilyn Monroe,” Papadopoulos told me. “They said, ‘You are an individual, George, that has tons of contacts in Athens and you are a subject of interest.’ ”

He said the two intelligence officers then asked about Moscow: “They were trying to find out why Trump was willing to work with Russia. They were trying to act as if they were pro-working with Russia.”

Around the same time, he said, an Israeli diplomat who portrayed himself as friendly to the Obama State Department, and decidedly opposed to Trump, befriended him in London. The Israeli official questioned him about where Trump stood on Russia and Iran issues, and introduced Papadopoulos to a woman he identified as his girlfriend.

That woman, Papadopoulos said, apparently worked for Australian intelligence and set up a meeting for him at a London bar to meet the Australian ambassador to England, Alexander Downer.

It was at that May 10, 2016, meeting that the FBI alleges Papadopoulos told Downer he knew the Russians had thousands of Clinton emails they planned to release later in the campaign. That release occurred in July, after which Downer reported his Papadopoulos information to U.S. authorities.

Papadopoulos said he doesn’t remember telling Downer about the email claim but does remember making a passing reference a few weeks later when he met the Greek foreign minister. “He basically told me, ‘Where you are sitting now, Putin will be sitting there tomorrow.’ And I just had this nervous reaction and said, ‘Oh, hey, I heard this thing about emails.’ It was nothing else.”

Whatever the case, the uninvited overtures continued in London.

The most significant, in Papadopoulos’s mind, was in September 2016 when Halper invited him to London to write an academic paper for $3,000.

A former adviser to Republican Presidents Nixon, Ford and Reagan, Halper was a respected professor at Cambridge University who frequented policy conferences deemed friendly to Western intelligence and diplomats. Two sources confirmed to me that the Washington Post article claiming Halper was a confidential human source who reached out to Papadopoulos at the FBI’s behest was true.

The sources said Halper reached out to other Trump campaign aides in the summer and fall of 2016, including Carter Page (who became the subject of the FISA warrant) and senior adviser Sam Clovis, though it is not clear if the FBI prodded him to do so. A spokesman for Cambridge and Halper did not immediately return a message seeking comment.

Papadopoulos said when he arrived in London for his meeting with Halper, strange things began to happen, beginning with the young woman who served as a guide. “She was trying to seduce me and was trying to hint that, ‘I want to sleep with you but you have to give some information first,’ ” he recalled.

Papadopoulos said he rejected that overture and then got another unexpected invite, this time from the British foreign ministry. He said two diplomats quizzed him about Trump’s positions on Iran, Russia and Brexit, and arranged a follow-up meeting with a more senior British official back in the United States.

Then, Papadopoulos recalled, Halper set up a meeting at a swanky London club fancied by diplomats. The conversation started with Halper challenging Papadopoulos on some of his views on the Middle East, but quickly turned to Russia.

“He puts his phone out in front of him and right away I saw what he was doing: this guy is obviously recording me,” Papadopoulos recalled.

At one point, Halper asked him about the hacked Clinton emails and “if I was involved and if the campaign knew,” he recalled.

Papadopoulos said he again denied involvement. “‘That would be treason. I don’t know what you are talking about and I have nothing to do with Russia,’” he recalled saying.

Papadopoulos said he does not believe he ever told anyone in the Trump campaign about the Russia emails, though he did offer to broker a summit between Trump and Putin — an idea that never gained traction with campaign insiders.

Democrats doubt Papadopoulos’s story about the emails. “It just stretches, I think, most people's credibility that if Papadopoulos had this knowledge and he wanted to try to further ingratiate himself with the campaign, that he wouldn’t have shared that with somebody on the campaign,” Senate Intelligence Committee Vice Chairman Mark Warner Mark Robert WarnerFBI director casts doubt on concerns over mail-in voting fraud Democrats call for declassifying election threats after briefing by Trump officials It's time to upgrade benefits MORE (Va.) said recently on CNN.

But some Republicans are convinced that Papadopoulos was targeted by a Western intelligence operation designed to discredit or infiltrate the Trump campaign, and that the Obama CIA may have played a role.

That suspicion is triggered by testimony that former CIA Director John Brennan gave to the House Intelligence Committee more than a year ago, when he acknowledged reaching out to the FBI in July 2016 to try to get an investigation started into Trump and Russia — even though he knew such an investigation was “well beyond my mandate” as CIA chief.

“I was worried about a number of the contacts that the Russians had with U.S. persons” in the Trump campaign, Brennan testified.

Whether the half-dozen Papadopoulos overtures by Western intelligence officials were directed or assisted by the CIA, or were purely coincidental, one important concern lingers: If Papadopoulos is telling the truth, the FBI possessed a critical piece of exculpatory evidence by September 2016 that called into the question the legitimacy of its Trump-Russia collusion probe.

If the FBI did not disclose that evidence to the FISA court a month later when it sought the surveillance warrant, it likely committed a grave abuse that furthers the narrative that this probe was infected more by politics than evidence.

And those who signed the FISA warrants — including Rosenstein — have serious questions to answer.

John Solomon is an award-winning investigative journalist whose work over the years has exposed U.S. and FBI intelligence failures before the Sept. 11 attacks, federal scientists’ misuse of foster children and veterans in drug experiments, and numerous cases of political corruption. He is The Hill’s executive vice president for video.

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