Donald Trump’s lawyer is expected on Thursday to resume attacking the credibility of Michael Cohen, the former attorney whose $130,000 hush-money payment to the adult film star Stormy Daniels is at the heart of the criminal trial against the former president.

The defense, led by the Trump lawyer Todd Blanche, previously undercut Cohen’s testimony by portraying him as an out-of-control witness, motivated to provide evidence that could see Trump convicted in an effort to exact retribution after he was left to fend for himself.

“Do you want President Trump to get convicted in this case?” Blanche asked on Tuesday. “Sure,” Cohen replied, keeping his composure under tense questioning about his falling-out with Trump after Cohen was charged by federal prosecutors in a related case in 2018 and Trump abandoned him.

That tenor of cross-examination is expected to continue as Cohen returns to the stand for a third day. Cohen is considered essential because he is the prosecution’s final witness and the only person to give evidence that Trump was involved in covering up the hush-money scheme.

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Trump has pleaded not guilty to 34 counts of felony falsification of business records. Prosecutors must prove Trump authorized what he knew to be hush-money repayments to be falsely characterized as “legal expenses” in the Trump Organization’s records, with an intent to commit a second, election crime.

The case against Trump – the first against a US president – stems from his attempts to suppress negative stories about alleged sexual encounters he had with Daniels and others for fear that they could negatively affect his campaign just weeks before the 2016 election.

Cohen has been a significant witness for the prosecution as he recounted how he used a home equity loan to raise $130,000, which he then wired to Daniels’ lawyer through a shell company he established. Cohen did so on the belief that Trump would reimburse him, he testified.

In January 2017, Cohen recounted, he discussed with Trump and the former Trump Organization chief financial officer Allen Weisselberg about being repaid for the $130,000, an overdue bonus and other expenses he incurred doing work that benefited the Trump 2016 campaign.

Cohen produced 11 invoices seeking payment pursuant to a legal “retainer” that did not exist, according to Cohen, that led to 11 checks being cut to Cohen and the Trump Organization recording 12 entries for “legal expense” on its general ledger – totaling 34 instances of alleged falsifications.

“Did Mr Weisselberg say in front of Mr. Trump that those monthly payments would be, you know, like a retainer for legal services?” Cohen was asked on direct examination on Tuesday. “Yes,” he replied, providing crucial testimony for the prosecution’s case.

Under New York law, prosecutors need to prove beyond a reasonable doubt that Trump either made or caused a false entry to be made in the business records of an enterprise. Cohen’s testimony provided the first direct evidence that Trump directed the nature of the reimbursement to be obscured.

But Cohen is also perhaps the most problematic witness for the prosecution because of his clear motivation to see Trump go to jail and the fact that he is a convicted liar, even if Cohen has insisted he lied only to protect Trump.

On cross-examination, Blanche attacked Cohen’s credibility by emphasizing his criminal record, implying he had initially sought some benefit from prosecutors in exchange for his cooperation. The jury could not tell where the truth ended and his embellishments began, Blanche appeared to suggest.