Judge Merchan told jurors that Michael Cohen is an "accomplice" to the alleged crime, so the jury cannot convict Trump on Cohen's testimony alone.

Even if they believe Michael Cohen, they need to rely on evidence corroborating his testimony, Merchan said.

Trump, at the defense table, appeared to perk up just a bit at this, looking up at Merchan as he delivered this information to the jury.

Judge Merchan told the jury that they have the ultimate authority in determining the truthfulness of a witness' testimony -- an instruction that might come in handy given the emphasis that defense lawyers placed on Michael Cohen's testimony, which they say includes lies.

"You will alone determine the truthfully and the accuracy of the testimony of each witness," Merchan said.

He added that the jury could either disregard the testimony of an untruthful witness entirely, or disregard part of it.

"There is no particular formula" to determine credibility, Merchan said.

"You may consider whether the witness has any interest in the outcome of the case," he said -- another matter that might weigh on jurors' minds.

"You may consider whether a witness did have, or did not have, a motive to lie," the judge said.

Trump's attorney had told the jury Cohen had an "axe to grind" against his former boss. Prosecutors partially conceded that Cohen had a motive, acknowledging that, to date, he is the only one who suffered any consequences from the matter at hand.

Trump, at the defense table, appeared to look over to the jury and offer a bit of a closed-mouth grin.

Judge Merchan instructed the jury that they cannot hold Trump's not testifying against him.

"Defendant is not required to prove that he is not guilty," he said.

"The defendant is not required to prove or disprove anything," said the judge.

Judge Merchan told the jury that they should not speculate about the sentence or punishment in the case.

"It will be my responsibility to impose an appropriate sentence," Merchan said.

The judge also had to advise the jury about this yesterday after defense lawyer Todd Blanche argued that the jury "cannot send somebody to prison" based on Michael Cohen's testimony.

The jury appears to be laser focused on Merchan during the charge. Half of the jurors appear to be taking notes.

While defense lawyers have talked plenty about an Oct. 24, 2016, phone call between Michael Cohen and Keith Schiller whose purpose they question, prosecutors have emphasized the importance of two other calls directly between Trump and Cohen on Oct. 26, 2016.

The day Cohen wired money from Essential Consultants LLC -- the bank account for the Stormy Daniels hush money payment -- Cohen spoke to Trump twice over the phone around 8 a.m. Prosecutors argued that Cohen got the go-ahead from Trump to make the payment on that call before he crossed the street from Trump Tower to wire money from First Republic Bank.

One call was three minutes long, and the other was about 90 seconds.

"This is damning, right?" prosecutor Josh Steinglass said. "Half an hour before that, he is getting the final go-ahead from Trump."

Steinglass said the "objective of the nondisclosure agreement with Stormy Daniels was to keep her quiet.

"It's no coincidence that the sex happened in 2006 but the payoff didn't happen until October 2016, two weeks before the election. That's because the defendant's primary concern was not his family, but the election," Steinglass said.

Trump, sitting at the defense table, shook his head in response.