The order came hours after Trump took to Truth Social to attack both Merchan and his daughter, calling the judge "a true and certified Trump Hater who suffers from a very serious case of Trump Derangement Syndrome."
The MAGA hopeful added, "His daughter is a senior executive at a Super Liberal Democrat firm that works for Adam 'Shifty' Schiff, the Democrat National Committee, (Dem)Senate Majority PAC, and even Crooked Joe Biden."
Trump's trial is set to begin April 15, a year after Manhattan District Attorney Alvin Bragg charged Trump with 34 counts of falsifying business records in relation to the hush money payments he made to adult film star Stormy Daniels prior to his 2016 campaign.
READ MORE: Gag order: Trump criminal case judge lays down the law
According to CNN, Merchan wrote that the ex-president is known to make "'threatening, inflammatory, denigrating' statements against people at all levels of the justice system, including jurors."
He added, "The uncontested record reflecting the Defendant’s prior extra-judicial statements establishes a sufficient risk to the administration of justice … and there exists no less restrictive means to prevent such risk."
MSNBC's Deadline: White House host Nicolle Wallace asked legal correspondent Lisa Rubin about her thoughts on Merchan's ruling in response to the ex-president's attack.
"I've been thinking about the timing of that gag order today," Rubin said. "Sometimes we hear from Judge Merchan, and we hear from him in rulings that actually happen days before, because he waits to release them.
“This one was written today and signed today and that's not accidental. It is not just because of Michael Cohen. It's not just because of what Trump said about one of the DA's lawyers yesterday.
“Trump took on Judge Merchan's own daughter today, and while she's not covered by this gag order, I still ask myself who would take this case? Who could take a case for someone in their social media communications threatens the daughter of a judge because of some loose association she has with the political party that you're opposing."
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She continued, "Trump is going to get great representation — I don't know that I would make that same decision," the attorney said, noting, "and certainly he has great lawyers here. But I keep struggling with — who would do that?"
Rubin asked, "Who would do that when your client is out there, not just attacking witnesses, not just attacking lawyers, but attacking the judge's own kid? These people have kids too."