By John Solomon

Opinion Contributor

In a 20-month search for evidence of collusion between Donald Trump's campaign and Russia, none that is compelling has emerged.

Former FBI Director James Comey told Congress he found none. The U.S. intelligence community has given a similar assessment, though it did prove convincingly that Moscow meddled in the 2016 election through cyber warfare. And, so far, special counsel Robert Mueller has not offered any collusion evidence, though his work continues.

But, for the first time, I can say there is evidence of collusion between Russians and Americans - specifically, the sort that is at the heart of counterintelligence work.

Before we review that evidence, let's define collusion. The Collins Dictionary says its original British meaning was "secret or illegal cooperation, especially between countries or organizations." Using that definition, collusion can be secret but good, if the outcome is well-intended. Or, it can be bad, if it is meant to defraud, deceive or create illegality.

Now for the evidence, as presented to me by several sources, American and foreign:

In September 2015, senior Department of Justice (DOJ) official Bruce Ohr and some FBI agents met in New York with Russian oligarch Oleg Deripaska to seek the Russian billionaire's help on organized crime investigations. The meeting was facilitated - though not attended - by British intelligence operative Christopher Steele.

In 2012, Steele's private firm, Orbis Business Intelligence, was hired as a subcontractor by a law firm working for Deripaska, who then headed Russia's largest aluminum company. Steele's firm was asked to do research to help the law firm defend a lawsuit filed against Deripaska by a business rival.

By 2015, Steele's work had left him friendly with one of Deripaska's lawyers, according to my sources. And when Ohr, then the associate deputy attorney general and a longtime acquaintance of Steele, sought help getting to meet Deripaska, Steele obliged.

Deripaska, who frequently has appeared alongside Russian President Vladimir Putin at high-profile meetings, never really dealt with Steele, but he followed his lawyer's recommendations and met with Ohr, my sources say.

By that time, Deripaska already had proven himself helpful to the FBI. As I've written previously, based on numerous U.S. sources, he cooperated with the bureau from 2009 to 2011 and spent more than $25 million of his own money on an FBI-supervised operation to try to rescue retired FBI agent Robert Levinson, who was captured in Iran while working as a CIA contractor.

U.S. officials and Levinson's family told me that Deripaska's efforts came close to securing Levinson's freedom before the State Department scuttled a deal. The former agent has never been heard from again.

The 2015 meeting between Ohr, the FBI and Deripaska is captured cryptically in some of Ohr's handwritten notes, recently turned over to Congress.

People familiar with the meeting said U.S. officials posed some investigative theories about suspected Russian organized crime and cyber espionage activity, theories that Deripaska indicated he did not believe were accurate.

The sources stressed that the 2015 meeting had nothing to do with any allegation about Russian meddling in the upcoming 2016 election but, rather, was an "outreach" about other types of suspected activity overseas that concerned U.S. officials.

A year later, Deripaska would get another visit from his FBI friends in New York. But this time the questions were about possible collusion between the Trump campaign and Russia. Specifically, the agents told Deripaska they believed Trump's former campaign chairman, Paul Manafort, was secretly coordinating the election with Moscow.

Steele had planted that theory with the FBI. By that time the former MI6 agent was working for the American opposition research firm Fusion GPS, which had been hired by Hillary Clinton's presidential campaign and the Democratic National Committee to find Russian dirt on Trump. Steele's theories, of course, are contained in the so-called Steele dossier provided to the FBI.

Ohr had his own connection to Fusion, which was paying his wife, Nellie, to work on the anti-Trump research project, according to congressional testimony.

Deripaska once had a business relationship with Manafort, but it ended in lawsuits. Despite that acrimony, Deripaska told the agents in that September 2016 meeting that he thought the theory that Manafort was colluding with Russia to help Trump win the election was preposterous.

Deripaska - like the many foreign business figures to whom U.S. intelligence has turned for help over the decades - is not without controversy or need. The State Department tried to keep him from getting a U.S. visa between 2006 and 2009 because they believed he had unspecified connections to criminal elements in Russia as he consolidated power in the aluminum industry. Deripaska has denied those allegations and claims FBI agents told him in 2009 that the State Department file blocking his entry to the country was merely a pretext.

Whatever the case, it is irrefutable that after he began helping the FBI, Deripaska regained entry to the United States. And he visited numerous times between 2009 and 2017, visa entry records show.

We now know that, on multiple occasions during those visits, the DOJ and FBI secretly collaborated with Deripaska in the hope of getting help, first regarding Levinson, then on Ohr's matters, and finally on the Manafort case. U.S. officials told me they assumed Deripaska let Putin's team know he was helping the U.S. government and that his motive for helping was to keep visiting America.

Today, Deripaska is banned anew from the United States, one of several Russians sanctioned in April by the Trump administration as a way to punish Putin for 2016 election meddling. But he wants to be clear about a few things, according to a statement provided by his team. First, he did collude with Americans in the form of voluntarily assisting and meeting with the FBI, the DOJ and people such as Ohr between 2009 and 2016.

He also wants Americans to know he did not cooperate or assist with Steele's dossier, and he tried to dispel the FBI notion that Russia and the Trump campaign colluded during the 2016 election.

"The latest reckless media chatter proposes that I had some unspecified involvement in the so-called dossier. Like most of the absurd fantasies and smears that ricochet across the internet, it is utterly false. I had absolutely nothing to do with this project, and I never had any knowledge of it until it was reported in the media and I certainly wasn't involved in any activity related to it," Deripaska said in the statement his team provided me.

Americans can form their own conclusions about the veracity of those claims. But they now have a pretty convincing case of collusion between U.S. officials and Russians, one that isn't necessarily all that harmful to the American interest.

And the tale of Ohr, Steele, Deripaska, the FBI and the DOJ is a cogent reminder that people looking for black-and-white answers on Russia are more likely to find lots of gray - the favorite color of the murky counterintelligence world.

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.