Things began to sour after the 2016 election, however, when Cohen did not receive an offer to be part of the Trump administration, where he had hoped to be appointed a chief of staff, a special counsel, or even attorney-general.

As Stormy Daniels’ former lawyer, Keith Davidson, told the jury earlier, Cohen called him a few weeks after Trump’s 2016 victory over Hillary Clinton, and was so despondent and shattered that “I thought he was going to kill himself”.

“I can’t believe I’m not going to Washington,” Davidson recalled Cohen saying in an expletive-filled rant. “I’ve saved that guy’s ass so many times, you don’t even know.”

From there, things went from bad to worse for the 57-year-old. In 2018, a few months after The Wall Street Journal broke the news of a cover-up of Daniels’ affair with Trump, Cohen’s home and offices were raided by the FBI, who seized documents relating to the hush money payments as well as personal, financial and banking records.

By December, he was sentenced to three years in prison for campaign finance violations, tax evasion and lying to Congress.

“Recently, the president tweeted a statement calling me weak – and it was correct but for a much different reason than he was implying,” an emotional Cohen said at the time. “It was because time and time again I felt it was my duty to cover up his dirty deeds.”

The dirty deeds allegedly included a hush money scheme that began in mid-2015, shortly after Trump announced he would run for president.

The court heard that was when Trump, Cohen, and tabloid mogul David Pecker, the publisher of the National Enquirer, hatched a plan to bury any potentially damaging stories that could derail the Republican’s campaign – a practice known “as catch and kill”.

Australian journalist Dylan Howard, who worked alongside Pecker as the editor of the National Enquirer at the time, was also a co-conspirator in the scheme, with text messages outlined in court showing how the pair regularly chatted via Signal, an encrypted phone messaging app, to keep sensitive matters private.

According to Cohen, Trump warned Cohen that when he announced his presidential campaign, there would be “a lot of women coming forward”. And soon enough, they did.

The first story they moved to bury came from a Trump doorman who alleged that Trump had a love child. Even though the story didn’t end up checking out, the doorman was paid $US30,000 by Pecker’s company, American Media Inc, to sign a non-disclosure agreement and bury the matter.

The second involved Karen McDougal, a former Playboy playmate who was paid $US150,000 by AMI to kill news of a months-long affair with Trump in 2006, when he was newly married to his wife, Melania.

And the third – which specifically relates to the 34 charges Trump now faces – involved the $US130,000 Cohen himself paid to Daniels by taking out a line of credit on his house and funnelling it through a shell company set up specifically to hide the payment.

Trump later reimbursed him by allegedly falsifying business records to disguise the hush money as a legal retainer.

Evidence presented to the court last week by the Trump Organisation’s former controller included handwritten notes he said were stapled to a bank statement with instructions for how the money would be paid out and how much Cohen would make on the payments.

According to Cohen’s testimony, Trump had ordered him to make the payment as the election day loomed, fearing that Daniels could tank his campaign – particularly following a damning Access Hollywood tape in which Trump was heard bragging about grabbing women by the genitals.

Cohen told the jury about the “catastrophic” impact they feared Daniels’ story could have on Trump’s chances of becoming president if it got out, and of Trump reportedly telling him that, while guys would “think it’s cool ... women are gonna hate me”.

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He also testified that Trump was intimately involved in the deal – “everything required Mr Trump’s sign-off”, Cohen said – and in a meeting the pair had with the Trump Organisation’s chief financial officer at the time to discuss the reimbursement.

And in evidence that caused Trump to shake his head vigorously, Cohen also recalled asking Trump how his wife might take everything that was happening – and that Trump, in turn, didn’t seem worried, saying he wouldn’t be “on the market” as a single man for long if she left.

“He wasn’t thinking about Melania,” Cohen said. “This was all about the campaign.”

The real test for Cohen, however, will come in the form of cross-examination by Trump’s lawyers later this week.

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Their plan is to rip his credibility to shreds and paint him to the jury as someone who has repeatedly changed his story and can’t be trusted.

Indeed, Cohen is such a problematic witness that he is part of the reason federal government authorities decided not to charge Trump earlier, leaving it to New York prosecutors to pick up the case instead.

Whether the volatile lawyer can stay calm in the face of hostile attacks could make all the difference in a case that could reshape the contours of the presidential election in November.

For now, however, Trump, despite his legal woes, remains on track to win, with a new poll by The New York Times and Siena College placing him ahead in five critical states: Michigan, Arizona, Nevada, Georgia and Pennsylvania.

“They’ve kept me here for 3½ to four weeks instead of campaigning, and yet we still have the best numbers,” Trump told reporters as court adjourned for the day. “It’s really a sad day for the country.”

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