Michael Cohen outside the federal courthouse in New York after pleading guilty to lying to CongressJulie Jacobson / Associated Press

In a Manhattan federal court on Thursday, President Donald Trump’s longtime personal lawyer Michael Cohen pleaded guilty to lying to Congress about the timing of his negotiations to build a Trump Tower Moscow in 2016, and about how often he discussed the deal with Trump during the campaign. The guilty plea is the first Mueller has secured that is related directly to Trump’s business dealings—and may be just the tip of the iceberg in the ongoing investigation of business deals involving the Trump Organization and Russian financiers, inside and outside the Kremlin.

With Trump now at war with someone who for years was his most loyal lieutenant and fixer, Cohen’s court appearance underscored the peril he presents for the president, who is unsettled by dramatic Democratic gains in the midterms and facing the prospect of unending offshoot probes by newly emboldened Democratic committee chairmen.

The plea includes evidence, for the first time, that could show how Trump was compromised by Russia while Russian President Vladimir Putin was waging a direct attack on the 2016 election. The formal agreement also incentivizes Cohen, the former executive vice president of the Trump Organization and Trump’s right-hand man for more than a decade, to tell Mueller everything he knows—and sets Cohen up as a more credible witness should Mueller ask him to testify in the future. Significantly, the guilty plea was finalized after Trump submitted his written answers to Mueller, who reportedly asked Trump specifically about the Moscow deal. (Trump’s lawyer, Rudy Giuliani, said on Thursday that Trump’s written answers matched the story that Cohen had told Mueller.)

Cohen, moreover, has indicated that he has no loyalty to the president and does not want or expect a presidential pardon. He has also not been sharing information with the president’s legal team throughout the course of his cooperation with Mueller, as Trump’s former campaign chairman Paul Manafort has been. Whereas Manafort has kept one foot in the door of Trumpworld, Cohen severed his ties to the president months ago. “The real wild card for Trump is Cohen,” said a veteran Washington lawyer who requested anonymity because he represents a client involved in the Russia probe. “It’s obvious that Cohen knows more about Trump’s business activities over the last decade than just about anyone.”

Cohen admitted on Thursday that he lied to Congress about how often he and Trump had spoken about the Trump Tower deal in 2016, and acknowledged that he had tried to organize a trip for Trump to Russia in 2016 to scope out the potential project after Trump clinched the Republican nomination. He lied both to minimize Trump’s link to the Moscow project and to limit “the ongoing Russia investigations,” according to Mueller’s team. The criminal information filed by Mueller’s office on Thursday makes clear that Cohen contacted the Kremlin “asking for assistance in connection with the Moscow Project” in January 2016.

Dan Goldman, a former federal prosecutor in the Southern District of New York, where he focused on organized crime, said he believes that the plea agreement is “a prelude to forthcoming indictments and other investigative steps. Before using information from a cooperating witness, prosecutors generally like to ‘lock in’ the witness through a guilty plea,” Goldman said. “So I would expect more to come arising out of, at least in part, Michael Cohen’s cooperation.”

It isn’t just Trump who may be in legal danger now that Cohen is cooperating—it’s also his family members, who Cohen admitted to briefing on the Trump Tower Moscow deal in 2016. According to the criminal information, filed by Mueller on Thursday, Cohen discussed the Moscow deal with Trump’s family members “within” the Trump Organization. Donald Trump Jr., an executive vice president of the Trump Organization, told the Senate Judiciary Committee last year that he was only “peripherally aware” of the Moscow deal in 2016. It is not clear what he told the House Intelligence Committee, which has not yet released the transcripts of the closed-door interview. But Representative Adam Schiff, the committee’s incoming chairman, said in a statement that the Cohen plea “highlights concern over another issue—that we believe other witnesses were also untruthful before our committee.”

While the extent of Cohen’s communications about the project with Trump’s family members is not laid out in the court filings, he has undoubtedly described those interactions to Mueller. “This sends a message that if you have lied to Congress, or plan to do so in the future, the special counsel will charge you for those lies,” Goldman said. “And the case is not simply a he-said, he-said: Mueller brings documentary proof to every one of his charges and allegations.” Indeed, the criminal information that Mueller filed against Cohen included emails that directly contradicted Cohen’s written statement to Congress. Goldman added that if he were Donald Trump Jr., “I would be more worried today than I was yesterday.”

Cohen’s guilty plea is the first Mueller has secured related directly to Trump’s business dealings, potentially crossing the “red line” Trump set last year related to his sprawling organization. Acting Attorney General Matthew Whitaker, who replaced Jeff Sessions earlier this month, has also said that Trump’s businesses should be off limits to Mueller.

But Cohen has been cooperating with Mueller’s team since August, when he first proffered information, and has already sat for more than 70 hours of interviews since September. That could prove to be incredibly damaging for Trump—who insisted both during and after the election that he had no business ties to Russia—and it could contextualize Trump’s consistent and inexplicable praise for Putin along the campaign trail. “This shows motive: Trump’s desire to pursue a major deal in Russia,” Jens David Ohlin, the vice dean of Cornell Law School, told me. “It finally gives Mueller some direct evidence that Trump’s associates continued to pursue business opportunities in Russia during the campaign, which would explain why Trump was, and continues to be, so deferential to Russia in general and Putin in particular. The motive was financial.”

Cohen also appears to be in a position to corroborate a key portion of the Steele dossier—a collection of reports written by the former British intelligence officer Christopher Steele outlining Trump’s alleged ties to Russia. Trump has called the dossier a collection of lies that was financed by Democrats.

Steele’s sources in Russia claimed that “the Kremlin’s cultivation operation” of the candidate had included offers of “various lucrative real estate development deals in Russia.” While Trump had a “minimal investment profile in Russia,” the dossier continued, it was “not for want of trying. Trump’s previous efforts had included exploring the real estate sector in St. Petersburg as well as Moscow.”

A top priority for some Democrats on the House and Senate Intelligence Committees has been to determine whether the Russians ever sought financial leverage over Trump and his associates, or whether they hold any such leverage today. Schiff, speaking to reporters, said that the criminal information filed Thursday raised the issue of “whether the Russians possess financial leverage over the president of the United States.”

“We need to look into the credible allegations that the Russians may have been laundering money through the Trump Organization,” Schiff said. “That has been a constant concern of ours, but an issue the Republicans were unwilling to look into. That is something we expect to pursue.”

Cohen’s guilty plea could shed light on the Trump family’s longtime bank of choice: Deutsche Bank, which was the only bank willing to loan to Trump after he lost others money in a series of bankruptcies. The bank was fined in 2017 as part of a Russian money-laundering scheme that involved its Moscow, New York, and London branches, and its headquarters were raided on Thursday morning by police and tax investigators as part of an ongoing money-laundering investigation. The bank refused last year to hand over documents requested by five Democratic lawmakers related to its relationship with Trump, citing the confidentiality of nonpublic customer information, and the GOP refused to subpoena the records.

Trump said on Thursday that he was still free to pursue business deals while he was running for president. “There was a good chance that I wouldn’t have won, in which case I would have gotten back into the business, and why should I lose lots of opportunities?” he told reporters. But he never disclosed the deal publicly, and Cohen’s guilty plea clearly shows how he lied in the written statement to the House and Senate Intelligence Committees to conceal the Trump Organization’s ongoing involvement in the Moscow project from January through June 2016, with the campaign under way.

The project wasn’t revealed until August 2017, when The New York Times obtained emails between Cohen and the Russian American businessman Felix Sater, who appears to be “individual 2” in the court documents filed on Thursday. Sater, who began advising the Trump Organization in the early 2000s and scoped out deals for it in Russia between 2005 and 2006, boasted of his ties to Putin in emails to Cohen in November 2015 and told Cohen that he could get “all of Putins team to buy in” on the Moscow deal. “Our boy can become president of the USA and we can engineer it,” Sater wrote. “I will get Putin on this program and we will get Donald elected.”

Sater forwarded a letter of intent to Cohen, outlining the terms of a licensing agreement to purchase property to build a “Trump World Tower Moscow,” and Trump eventually signed it. Cohen was also in touch with an assistant to Putin’s right-hand man, Dmitry Peskov, according to the court filings, and was apparently invited to be Peskov’s guest at the St. Petersburg Forum in June 2016. Cohen told Sater he would attend, but backed out at the last minute—just days after senior members of the Trump campaign met with a Russian lawyer at Trump Tower on the promise of obtaining dirt on Hillary Clinton. Peskov himself, meanwhile, also appears to have been caught in a lie: While he acknowledged on Thursday that his office called Cohen in 2016 to discuss the Trump Tower Moscow project, he claimed last year that the Kremlin had never replied to Cohen’s overtures because “we do not react to such business topics.”

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