Donald Trump’s social media posts about likely witnesses will be the first order of business Tuesday when court is back in session for the historic criminal trial of a former president.

The day is scheduled to begin with a hearing about whether Trump should be held in contempt over a series of posts on Truth Social that prosecutors argue violated a gag order New York state Judge Juan Merchan issued this month prohibiting him from publicly attacking witnesses and jurors. Manhattan District Attorney Alvin Bragg’s office is also likely to cite comments Trump made to reporters Monday, when he repeatedly called Michael Cohen, an expected key witness, a liar.

The DA’s office is seeking the maximum $1,000 fine for each of the 10 posts it says violated the order, along with an order that Trump remove the posts from his social media platform. It also wants Merchan to warn Trump any future violations risk not just additional fines but also as long as 30 days in jail.

Trump attorney Todd Blanche contends his client hasn’t violated the April 1 order.

It’s not clear exactly when Merchan will rule on the prosecution’s motion; a decision could come as early as Tuesday.

After the hearing, the jury will be brought back into the courtroom for further testimony from David Pecker, the former publisher of the National Enquirer, who was the first witness the DA’s office called Monday. During his opening statement, prosecutor Matthew Colangelo said Pecker conspired with his longtime friend Trump and Cohen, who was then Trump’s lawyer, in a scheme to suppress scandalous stories about Trump during his 2016 presidential campaign.

“They agreed that Pecker would help the defendant’s campaign by acting as eyes and ears for the campaign,” Colangelo said.

It was Pecker who alerted Cohen to the news that adult film star Stormy Daniels was about to come forward with a claim that she had had a sexual encounter with Trump in 2006, when he was married, Colangelo said. Trump has denied her claim.

Pecker’s testimony Monday was brief — he was on the stand for just about 20 minutes before court ended for the day. He’s expected to get into the details of his relationship with Trump and the alleged conspiracy when he returns to the stand at about 11 a.m. ET Tuesday.

Cohen ultimately paid Daniels $130,000 to get her to sign a nondisclosure agreement. Prosecutors allege that Trump falsely claimed his reimbursement to Cohen as legal payments. He’s charged with 34 counts of falsifying business records, a low-level felony, and faces up to four years in prison if he’s convicted. He has pleaded not guilty.

The contempt hearing scheduled for Tuesday morning will focus on prosecutors’ allegation in two court filings that Trump “willfully violated” the gag order with repeated posts on Truth Social. The cited posts include one that referred to Cohen and Daniels as “sleaze bags” and others that linked to a New York Post story calling Cohen a “serial perjurer.”

The partial gag order Merchan slapped on Trump this month bars him from making “public statements about known or reasonably foreseeable witnesses concerning their potential participation in the investigation or in this criminal proceeding.”

Trump’s attorneys have argued that the posts didn’t violate the order because he was largely sharing posts from other people and news outlets. They also contend that the order allows Trump to defend himself from attacks, so he was within his rights to speak out because Cohen and Daniels have criticized him publicly. Merchan said last week that he doesn’t believe his order makes such an exception.