Michael Cohen worked for years as Donald Trump's fixer, a problem solver who was involved in every aspect of the real estate tycoon's business, even saying he would "take a bullet" for the billionaire.
But the once-loyal lieutenant has become Trump's biggest headache, appearing as the key witness for the prosecution in the ex-president's historic criminal trial.
Cohen turned on Trump in 2019, giving blistering testimony to Congress that the then-president was a "conman" who ordered him to pay a porn star hush money during a presidential campaign.
That transaction is at the heart of the New York trial, in which Trump's defense is seeking to discredit Cohen -- who has since had his law license revoked and spent time in prison -- as a witness lacking credibility.
Asked Monday by a prosecutor whether he had lied and bullied people on behalf of Trump, the 57-year-old told the Manhattan court: "Yes... It was what was needed in order to accomplish the task."
Cohen appears to be on a personal quest to see Trump punished, and has been skewering the former president on social media, prompting Judge Juan Merchan to ask him to stop publicly attacking the defendant.
Cohen recently posted on TikTok an image of himself wearing a t-shirt that appeared to show Trump behind bars in an orange prison suit.
"Trump 2024? More like Trump 20 to 24 years," Cohen, who himself spent over a year in prison, said in another clip.
Six years ago in federal court Cohen said he paid adult film actress Stormy Daniels -- who claims to have had a sexual tryst with Trump -- $130,000 "at the direction" of Trump in order to keep her story under wraps, and that Trump later reimbursed him.
Then in nationally televised testimony before a US House committee in 2019, he described how he made threats to journalists who asked too many questions about the shady dealings of a man whose empire was built on loud, cocky and grandiose self-promotion.
Working for a decade at Trump's side, Cohen was eventually named vice president of The Trump Organization, the fixer assigned the most delicate tasks his boss needed done.
This devotion would earn Cohen -- the son of a nurse and a Polish-born doctor who survived the Holocaust -- the nickname of Trump's pitbull.
Before Congress, he expressed regret for his years of devoted service to the real estate tycoon, for doing "bad things," and for succumbing to "the intoxication of Trump power," as he described it.
"I am ashamed of my weakness and misplaced loyalty -- of the things I did for Mr. Trump in an effort to protect and promote him," Cohen told lawmakers.
Behind closed doors Cohen was a key witness in the investigation into Russian interference in the 2016 US election and whether Trump's campaign colluded with Russia to sway the presidential vote in his favor.
From May 2019, Cohen spent 13 months behind bars and a year and a half under house arrest, after he was sentenced to three years' imprisonment for lying to Congress and for financial crimes.
After graduating from law school at Western Michigan University, Cohen specialized in representing people hurt in accidents -- an ambulance chaser in slang.
Along with his Ukrainian-born wife, Cohen later made a great deal of money investing in New York taxi licenses, in a pre-Uber era when their value was high and always climbing.
As Trump's personal attorney, Cohen admitted, he arranged for hush money payments before the 2016 election to Stormy Daniels and former Playboy Playmate Karen McDougal, both of whom claimed to have had sex with Trump.
Trump's team is seeking to discredit Cohen as a serial liar who aimed to monetize his campaign against his former boss with books and a podcast.
On his podcast, "Mea Culpa," Cohen spoke with Stormy Daniels, apologizing for the "needless pain" he caused her when coordinating the hush money payment.
Daniels in her conversation with Cohen offered graphic descriptions of her alleged 2006 sexual encounter with Trump, calling it the "worst 90 seconds of my life."
