NEW YORK Michael Cohen, who once said he would take a bullet for Donald Trump, is now poised to serve as a star prosecution witness in the former US president's criminal trial on charges of covering up hush money paid to a porn star.

Cohen's role at the first criminal trial ever of a US president, which began on Monday in New York state court in Manhattan, marks the culmination of his 15-year arc from being the businessman-turned-politician's lawyer and "fixer" to an outspoken antagonist.

"I'm the guy who would take a bullet for the president," Cohen told Vanity Fair in 2017.

The case stems from Cohen's US$130,000 payment to porn star Stormy Daniels before the 2016 election for her silence about a sexual encounter she had with Trump a decade earlier. Cohen, formerly a top executive at Trump's real estate company before becoming his lawyer, says Trump directed the payment.

Trump, the Republican presidential candidate in the Nov 5 election, has pleaded not guilty to 34 counts of falsification of business records to conceal the payment. He has also denied the encounter with Daniels, whose real name is Stephanie Clifford, and called Cohen a "serial liar".

Cohen turned on Trump midway through his presidency, as federal investigators probed his role in the Daniels payment and other matters.

In 2019, Cohen testified before a US congressional committee and said, "I am ashamed because I know what Mr Trump is. He is a racist. He is a con man. He is a cheat."

After Trump's 2023 indictment, Cohen said his goal in cooperating with authorities was to "speak truth to power".

"If speaking truth to power makes me Donald's archnemesis, so be it," Cohen told Reuters in a 2023 interview.

This will not be Cohen's first time testifying in court against Trump. In a civil fraud case over the former president's valuations of his real estate assets, Cohen said on the stand in October he had manipulated the values of Trump's real estate properties to match "whatever number Mr Trump told us."

A judge in February ordered Trump to pay US$454 million in penalties and interest after finding that he misled lenders and insurers about the Trump Organization's property values.

Three-year prison sentence

Cohen was hired as the Trump Organization's executive vice president and special counsel in 2007. Before that, the Long Island native and son of a Holocaust survivor worked as a malpractice lawyer and owned a fleet of yellow taxis.

He was hired after he had orchestrated the ouster of the board of directors of a condominium where he owned an apartment, which was trying to remove Trump's name from the building's exterior.

Cohen later advised Trump's 2016 presidential campaign and, as his personal lawyer, remained close to Trump once he became president, though he did not have an official White House job.

In 2018, after the hush money payment to Daniels came to light, Cohen initially said he had paid with his own money and that neither the Trump campaign nor the Trump Organization reimbursed him.

He later pleaded guilty to a federal campaign finance law violation for paying Daniels and then testified in Congress that Trump told him to make the payment. He said he was reimbursed in installments and displayed a copy of a US$35,000 cheque from Trump's personal bank account.

Cohen was sentenced to three years in prison for the payment and other crimes, including cheating on his personal taxes and lying under oath to Congress about when the Trump Organization stopped working on a proposed building project in Russia. Cohen served more than a year before being released.

'Part of the playbook'

Relying on Cohen's testimony presents risks for Manhattan District Attorney Alvin Bragg, given the disbarred lawyer's history of false statements.

Cohen's testimony at the civil fraud trial could provide fertile ground for Trump's defence lawyers during cross-examination at the criminal trial. At the civil trial, he said he lied to the federal judge who took his guilty plea in 2018 by admitting to tax fraud - a crime he now says he did not commit.

Cohen, who is married and has two children, has said he has taken responsibility for his wrongdoing. He has also said much of his criminal conduct - including the lie to Congress and the Daniels payment - arose out of his blind loyalty to Trump.

He told Reuters in the 2023 interview he expected Trump and his allies to attack him.

"It's all part of the playbook," Cohen said.
 

  - Reuters