From the start, the defense team, which unlike the prosecution does not have the burden of proof in the case, has sought to cast Cohen as a disgruntled ex-employee out for blood -- and Thursday is their big chance to nail it down.
Meanwhile Trump, the first former US president to be tried criminally, has complained that his current effort for another White House term is stymied by the court proceedings.
He's taken to bringing an entourage of Republican lawmakers and higher-ups to trial, aiming to bring the campaign to the courtroom and increasingly brand the case as politicized.
Trump faces 34 felony counts of falsifying business records with the intent to further other crimes in the run-up to 2016's presidential election.
Todd Blanche began questioning Trump's fixer-turned-foe on Tuesday afternoon under the watch of his high-profile client.
After an aggressive start, his line of questioning dulled and meandered as the afternoon wore on, with yawns betraying some jurors' fatigue.
The defense attorney was largely deferential when the witness -- himself a former lawyer who is not unfamiliar with courtroom strategy or proceedings -- sought to evade direct answers.
Cohen has a reputation for a temper that could hurt him on the stand -- his testimony during Trump's civil fraud case last year proved chaotic -- but on Tuesday he was mostly measured in responding to Blanche's questions, which at times veered convoluted.
After a day off the defense will resume Thursday morning, and it's possible they're saving their heat for when the jury has had some rest.
Prosecutors have indicated that Cohen, 57, is their last witness in the case.
His story has generally lined up with those of two other key witnesses: Stormy Daniels, the adult film star who says she received the hush money, and David Pecker, the one-time tabloid boss who said he worked with Trump and Cohen to suppress negative coverage of the White House hopeful during his first campaign.
- Will Trump testify? -
Trump is accused of falsifying business records to reimburse Cohen for a $130,000 payment to Daniels before the 2016 election, when her account of a sexual encounter with the then-Republican nominee could have doomed his campaign.
He denies that the one-night stand with Daniels occurred.
After the prosecution rests, the defense has the opportunity to present a case, though they're not required to and have not specified whether they will.
Most importantly Trump's lawyers have remained vague on whether their client will testify.
The businessman famously considers himself his own best champion -- but analysts widely believe that he could be a major liability on the stand.
When the jury is given the case for deliberation, the weeks of oft-salacious testimony will likely linger front-of-mind, but they'll also have stacks of documents to pore over.
The interpersonal relationships of the characters in the case make it juicy, but at the end of the day the charges hinge on financial records, and whether falsifying them was done with the intent to sway the 2016 presidential vote.
Prosecutors this week painstakingly detailed the alleged crimes, walking Cohen and the jury through the issue of 11 checks -- most signed by Trump -- in return for invoices Cohen said were falsified to cover up the hush money reimbursement.
Cohen said he had made the payments "to ensure that the story would not come out, would not affect Mr Trump's chances of becoming president of the United States" and did so "on behalf of Mr Trump."
Cohen spent 13 months in jail and another year-and-a-half under house arrest after pleading guilty in 2018 to lying to Congress and committing financial crimes.
Under direct questioning he said Trump had reassured him after FBI agents, seeking evidence in the case, raided his hotel room and office in April 2018.
"Don't worry, everything's going to be fine, I'm the president of the United States," Cohen recalled Trump saying.
"I felt reassured because I had the president of the United States protecting me," Cohen testified.
