U.S. District Court Judge Lewis A. Kaplan warned former President Donald Trump after he spoke out in front of a jury hearing a defamation case against him Wednesday.

On the second day of the trial, writer E. Jean Carroll testified about how she had been defamed after Trump denied raping her.

During Carroll's testimony, Trump was heard muttering loud enough for the jury to hear.

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"With the jury out of the room, Carroll's lawyer Shawn Crowley is complaining that Trump is muttering loud enough that the plaintiff's table can hear him," Politico's Erica Orden reported. "Crowley says Trump is saying Carroll's testimony is false and suggesting she has 'suddenly gotten her memory back.'"

Before taking a break from the trial, Kaplan suggested he would address Trump's remarks.

"What about Mr. Trump being vocal in the presence of the jury?" the judge asked. "I'm just going to ask that Mr. Trump take special care to keep his voice down when he's conferring with counsel so that the jury does not overhear it."