Yana Paskova/Getty Images(NEW YORK) — Michael Cohen, President Donald Trump’s former longtime personal attorney, has tentatively reached a plea agreement with federal prosecutors in the Southern District of New York, ABC News has learned.

Given Cohen’s proximity to Trump during the past decade, including throughout his meteoric rise from mogul and reality television star to the White House, observers consider him one of most potent legal thorns to confront Trump’s presidency since he took office.

“The guy who knows where all the bodies are buried,” said Seth Hettena, an author and veteran journalist who has chronicled Trump’s business career.

The investigation into Cohen was referred to New York’s Southern District by special counsel Robert Mueller, and if Cohen agrees to cooperate, the information he provides could benefit the investigation into Russian meddling in the 2016 election. But it remains unclear if he has committed to cooperate.

Cohen’s relationship with Trump dates to the mid-2000’s after Cohen, who owned condominiums in multiple Trump buildings in New York, took Trump’s side in a legal dispute with the condo board at Trump World Tower on Manhattan’s East Side. Cohen eventually went to work for the Trump Organization, where he held the positions of executive vice president and special counsel to Donald J. Trump.

“Michael Cohen has great insight into the real estate market,” Trump said of Cohen in a 2007 New York Post interview. “He has invested in my buildings because he likes to make money – and he does.”

In addition to working inside the Trump Organization as a lawyer and problem solver, Cohen built a diverse portfolio of investments.

At one point that included running 260 yellow cabs with a Ukrainian-born partner – a partnership that ended in 2012. He also invested millions in real estate, often turning a tidy profit. For instance, a building he bought in 2011 on the Lower East Side of Manhattan for $2.1 million, sold three years later for $10 million in cash.

The FBI raid on Cohen’s home and office in April gave the most significant indication his business dealings could become a legal problem for him.

Then in May, Evgeny Friedman, 46, a Russian immigrant known as the “Taxi King,” struck a plea deal that included a commitment to assist federal prosecutors investigating Cohen’s business practices.

At the time, veteran defense attorney Michael Volkov, who is not tied to this case, told ABC News he thought that spelled trouble for Cohen’s legal prospects.

“The government now has a strong inside witness who can assist in explaining many of Cohen’s business activities and potential fraud schemes, especially when it came to valuing the medallions for loan purposes,” Volkov said at the time.

In a Tweet shortly after Friedman’s plea arrangement, Cohen sought to distance himself from Friedman.

“I am one of thousands of medallion owners who entrust management companies to operate my medallions according to the rules of the NYC Taxi and Limousine Commission,” Cohen wrote. “Gene Freidman and I are not partners and have never been partners in this business or any other.” Hettena, author of the book Trump/Russia: A Definitive History, said Cohen’s legal trouble is not a surprise to anyone who closely studied his legal career.

“This is a pattern with him,” Hettena said. “This is a guy who is willing to cut corners. To bend rules. Whatever is going to help whatever interest he is serving.”

For more than a decade around the office in Trump Tower – and around New York – Cohen’s loyalty to Trump was unquestioned as he developed a reputation as Trump’s “pit bull.”

“It means that if somebody does something Mr. Trump doesn’t like, I do everything in my power to resolve it to Mr. Trump’s benefit,” Cohen said in a 2011 interview with ABC News. “If you do something wrong, I’m going to come at you, grab you by the neck and I’m not going to let you go until I’m finished.”

In 2010, Cohen was among the creators of a website, ShouldTrumpRun.org, that sought to encourage the New York real estate tycoon and reality television star to pursue a challenge to President Barrack Obama in the 2012 election.

“I think the world of [Trump],” Cohen told ABC News in the 2011 interview. “I respect him as a businessman, and I respect him as a boss.”

Cohen’s dealings at the Trump family business covers a broad sweep of its global empire – including several projects that have caught the attention of federal investigators. Cohen played an integral role in early discussions about a possible Trump Tower in Moscow – negotiations that were going on during the early months of the 2016 presidential campaign.

That deal never reached fruition.

Cohen has confirmed he attended a lunch meeting with a Ukrainian politician one week after Trump took office, where the two men discussed the potential for Cohen to share a Ukraine peace proposal with his contacts at the White House. “He could be extremely valuable,” said Matthew G. Olsen, a former federal prosecutor and ABC News contributor. “He was not just a personal lawyer but also was President Trump’s so-called fixer for a number of years. So he would have had access to lots of very personal information involving his business dealings.”

Cohen’s name appeared repeatedly in the now infamous dossier of unverified allegations, which included salacious claims about Trump, prepared by former British intelligence agent Christopher Steele.

The agent, who was hired by Fusion GPS, an opposition research firm that was paid initially by Republicans and later by Democrats, alleged in the dossier that Cohen was involved in attempting to covering up contacts between Russian operatives and members of Trump campaign, according to the document.

Cohen fiercely denied the claims.

In January, he tweeted “Enough is enough of the #fake #RussianDossier” before filing a lawsuit against Buzzfeed, the news outlet that first published the document – a suit he later withdrew.

In January – the Wall Street Journal first revealed Cohen’s role in negotiating a secret non-disclosure agreement with adult-film actress Stephanie Clifford, aka Stormy Daniels. The deal – which was executed less than two weeks prior to the November presidential election – paid Daniels $130,000 in exchange for her silence.

Government watchdog groups quickly filed complaints with the Federal Election Commission and the Department of Justice, asking the agencies to investigate for possible violations of campaign finance law.

Following the disclosure of the Daniels’ deal, Cohen insisted that he had acted on his own in the Daniels deal and that he had not been reimbursed by the campaign or the Trump Organization.

He told ABC News that the funds used to pay Daniels came from an existing home equity line of credit.

Two sources familiar with the search warrant that led to the raids on Cohen properties told ABC News in April that federal agents were hunting for records tied to Cohen’s personal business dealings and secret deals with Trump’s alleged mistresses, media organizations during the 2016 presidential campaign.

On April 5, four days before the authorities raided Cohen’s properties in New York, President Trump told reporters on Air Force One that he didn’t know why Cohen had paid Daniels or where he had gotten the money to pay her. The president later acknowledged, in a financial disclosure form filed last month with the Office of Government Ethics, that he had reimbursed Cohen.

Then there is Karen McDougal, who in August 2016 signed a $150,000 deal with American Media Inc., the publisher of the National Enquirer, that transferred to the company the rights to her story of an alleged ten-month romantic affair with Trump in 2006. The magazine never published her story. McDougal alleged in a lawsuit filed earlier this year that Cohen had allegedly conspired with her former attorney to bury the story. McDougal settled her lawsuit.

President Trump, through his representatives, has denied the allegations of McDougal and Daniels.

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