Following the break, former Trump attorney Michael Cohen has entered the courtroom.

He took his seat in the witness box to resume his cross-examination as Trump looked on.

Defense attorney Todd Blanche asked to approach the bench about an ongoing discovery issue.

Both legal teams leaned in as Blanche spoke to the judge.

With the sidebar completed, the judge called for a ten-minute break.

Judge Merchan denied a request from defense lawyers to broaden the scope of testimony from their expert witness Bradley Smith, who is an expert on campaign finance regulations.

On Thursday, defense lawyers asked Merchan to allow Smith to testify about various terms related to federal campaign finance laws. Merchan denied the request, citing long standing precedent prohibiting witness testimony about the law.

"An expert is not permitted to present or interpret the law," Merchan said.

Merchan also expressed concerns about Smith's testimony prompting a "battle of the experts" between Smith and an expert called by prosecutors, which Merchan said would confuse the jury.

Merchan said that Smith could still testify, as long as he follows the limits imposed in his pretrial ruling on the case's motions in limine.

"The court will monitor this testimony closely to ensure full compliance," Merchan said in a pretrial ruling. "Any deviation from this ruling could result in sanction up to and including striking the expert's entire testimony."

Trump, sitting at the defense table, shook his head after the judge announced his ruling.

Judge Merchan has begun hearing arguments about the admissibility of some defense exhibits, including an email communication between Michael Cohen and his one-time attorney Bob Costello's law partner Jeffrey Citron.

Defense attorney Todd Blanche argued that the exhibit could be used to impeach Cohen's testimony.

Judge Merchan said he will not allow the email into evidence. Prosecutors argued that the email was hearsay and cannot fairly offer a window into Cohen's state of mind.

"There is another layer there of hearsay," Merchan said about the email. "I don't see any probative value for impeachment purposes here at all."

Defense witness Robert Costello, who for a time was Michael Cohen's attorney, introduced details of his first meeting with Cohen, saying they first met at the Regency Hotel in Manhattan on April 17, 2018, with attorney Jeffrey Citron.

Cohen "was absolutely manic" during the first meeting, Costello said. The FBI had just raided his home and office.

“I really want you to explain what my options are. What’s my escape route?” Costello said Cohen told him.

Cohen said, "My life is shattered, my family's life is shattered," Costello testified.

Costello said he told Cohen, “This entire legal problem he was facing would be resolved by the end of the week if he had truthful information about Donald Trump and cooperated with the Southern District of New York.”

Costello said that Cohen on multiple occasions said, “I swear to god Bob, I don’t have anything on Donald Trump.”

"Did the topic of Stormy Daniels come up?" defense attorney Emil Bove asked Costello.

Costello said it did, with Cohen telling him, "I don’t understand why they’re trying to put me in jail for some f------ NDAs."