Inside a dreary Lower Manhattan courtroom on a recent Wednesday, Justice Juan M. Merchan convened a special session for people with mental health troubles who had landed in legal jeopardy. He calmly counseled them, praised any signs of progress and shook the hand of one man who, thanks to medication, had turned his life around.
But on April 15, a different type of criminal defendant will enter the same courtroom and test the judge’s equanimity: Donald J. Trump.
Mr. Trump’s trial on charges that he covered up a sex scandal before and after the 2016 presidential election will bring a weekslong maelstrom that no other judge in New York’s vast judiciary has ever experienced. It will be the first prosecution of a former U.S. president, a man who revels in attacking the legal system and its judges.
Since the Manhattan district attorney charged Mr. Trump last year, the former president has used campaign emails, social media invective and repetitive legal filings to attack the judge’s integrity and family. Last week, the former president demanded for a second time that Justice Merchan step aside, citing his daughter’s position at a Democratic consulting firm that worked for the 2020 Biden campaign.
Known as a no-nonsense, drama-averse jurist, Justice Merchan, 61, could reject the recusal request in the coming days, as he has so many of Mr. Trump’s last-ditch bids to delay the trial. The judge, who has already reprimanded Mr. Trump’s lawyers for arguments that he considered frivolous, has also issued a gag order to protect prosecutors, witnesses and his own family from Mr. Trump’s vitriol — and yet the former president has continued to post articles with pictures of the judge’s daughter.
The turmoil punctuates the former president’s yearslong assault on the judiciary, an antipathy that intensified with his political rise and mounting legal peril. Facing four criminal indictments in four different cities, he has demonized the judicial system, stoking anger in his base as he seeks to retake the White House as the presumptive Republican nominee this year.
Although Justice Merchan is a registered Democrat, records show he was previously a Republican, and people who know him described the judge as a moderate, law-and-order former prosecutor.
Two people close to Justice Merchan, who spoke on the condition of anonymity, said that the judge had privately expressed pain over the attacks on his daughter, but the people said that those attacks won’t compromise his ability to oversee the case. Other people who know the judge said that he will cast aside Mr. Trump’s drama — and exert control over the trial.
“It is Judge Merchan’s show,” said Jill Konviser, a retired judge who has known Justice Merchan for more than 15 years. While declining to discuss Justice Merchan’s personal feelings, she added: “He will do everything he can to, one, control his courtroom and two, ensure a fair trial for the defendant.”
Ms. Konviser acknowledged, however, that Mr. Trump is “not like every other defendant,” adding, “He’s the former president of the U.S., and he has chosen to make this process eminently more challenging.”
The former president often directs his harshest condemnations at judicial officials who are women or minorities, including Justice Merchan, who was born in Bogotá, Colombia, but raised primarily in Queens, as Mr. Trump was.
In 2016, Mr. Trump attacked Gonzalo P. Curiel, who was handling a fraud case involving Mr. Trump’s for-profit education venture, referring to him as “a Mexican judge” and demanding his recusal partly because of his heritage.
Tanya Chutkan, who oversees a federal case in Washington accusing the former president of plotting to overturn his 2020 election loss, is Black. Mr. Trump has called her “a fraud dressed up as a judge.”
And last year, Mr. Trump targeted the principal law clerk of the judge in a Manhattan civil fraud trial, posting a photo of the clerk next to Chuck Schumer, the Senate majority leader, and falsely calling her “Schumer’s girlfriend.”
One of the few judges to escape his ire is Aileen Cannon, the federal judge in Florida who is presiding over a criminal case in which he is accused of mishandling classified documents. Mr. Trump praised her as “highly respected.” He had appointed her.
In Justice Merchan’s 17 years on the bench, 13 as presiding judge in the Mental Health Court he created, he has had his share of unusual cases. There was a murder trial involving a supposed curse on the defendant; the daredevils who jumped off the World Trade Center with parachutes; and a so-called soccer-mom madam accused of running a high-end brothel on the Upper East Side. In that case, an appeals court reduced the steep bail Justice Merchan had set, calling it “unreasonable.”
None of those defendants challenged the judge quite like Mr. Trump, who for decades has navigated around law enforcement scrutiny. He fended off a federal investigation into a 1970s-era land acquisition; survived a special counsel examination of his campaign’s possible ties to Russia; and faced two presidential impeachments. Even now, facing four indictments, Mr. Trump is delaying three of the cases, much to prosecutors’ dismay.
Yet Justice Merchan, who declined to comment for this article through a spokesman, is pushing the Manhattan case forward.
In the case, the district attorney, Alvin L. Bragg, has accused Mr. Trump of falsifying business records to conceal a sex scandal that threatened to derail his election victory in 2016. It will be the first of the four criminal cases against the former president to go to trial and will take place in the city where he made his name and fortune.
That has infuriated Mr. Trump, who claims that the case is a witch hunt. On Saturday afternoon, he declared that Justice Merchan’s gag order had infringed on his First Amendment rights.
“He’s got me GAGGED, because he doesn’t want the FACTS behind the Gag to come out,” the former president posted on social media.
Justice Merchan is not the first judge to restrict Mr. Trump’s comments. Judge Chutkan did, as did the judge overseeing the civil fraud case. Unlike them, Justice Merchan amended his gag order to cover attacks on his own family, doing so at Mr. Bragg’s request.
The former president has tested the order’s limits by posting articles that named and attacked Justice Merchan’s daughter, Loren, and his wife, Lara. The articles, by the conservative activist Laura Loomer, included photos of Loren Merchan and copies of a 2007 mortgage statement for a house owned by Justice Merchan and his wife. Previously, Mr. Trump falsely accused Loren Merchan of posting an image of him behind bars on social media.
The posts came the same week Mr. Trump’s lawyers asked that Justice Merchan recuse himself.
Mr. Trump’s lawyers also sought the judge’s recusal last year, citing his daughter’s work and the judge’s own modest political donations. They noted that, during the 2020 presidential campaign, Justice Merchan had given $15 to Mr. Biden and $10 to a group called “Stop Republicans.”
In a statement, a spokesman for Mr. Trump’s campaign, Steven Cheung, claimed the judge was “politically compromised” and “should do the right thing and immediately recuse himself in order to show the American people that the Democrats have not destroyed our justice system completely.”
Yet Mr. Bragg’s prosecutors urged the judge to reject the request, calling Mr. Trump’s only evidence “a daisy chain of innuendos.” They noted that a state advisory committee on judicial ethics had already determined that Justice Merchan’s impartiality could not reasonably be questioned based on his daughter’s interests or his contributions. Such donations are common in New York judicial circles, where almost everyone is a Democrat.
And in interviews, several ethics experts disputed the idea that Loren Merchan’s career posed a conflict.
“If we forced the disqualification of a judge every time a close relative had a political interest in the outcome of a case the judge was assigned, the administration of justice would grind to a halt,” said Charles Gardner Geyh, a former special counsel for the Administrative Office of U.S. Courts and a professor at Indiana University’s law school.
Still, the judge’s donations could give the appearance of conflict.
“In the court of law, Judge Merchan was well within his rights and ethical guidelines to have made these small donations four years ago,” said Anthony Coley, a former head of public affairs at the Justice Department under Mr. Biden who is now an NBC News legal analyst. “But in the court of public opinion, appearances still matter.”
Justice Merchan, who was once an internal auditor at a real estate firm, has often served in nonpartisan roles. He started his legal career as a prosecutor in the Manhattan district attorney’s office before joining the New York attorney general’s office, where he handled a variety of cases, including financial crimes. Later, he was appointed to Bronx Family Court by Mayor Michael R. Bloomberg, a Republican at the time. And although he was confirmed by the State Senate to serve on the Court of Claims, in 2009, New York’s chief administrative judge appointed Justice Merchan to the bench in Manhattan.
This is not Justice Merchan’s first Trump-related trial. In 2022, he oversaw a criminal tax fraud case involving the Trump Organization. Following a jury conviction, Justice Merchan fined the company the maximum possible amount, $1.6 million.
The judge also sentenced Mr. Trump’s longtime finance chief, Allen H. Weisselberg, to five months at the Rikers Island jail complex. Privately, people with knowledge of the matter have said, the judge informed Mr. Weisselberg’s lawyers that he takes white-collar crime seriously.
In Mr. Trump’s own case, Justice Merchan has been firm, exercising tight control over pretrial hearings and reining in any bubbling drama. During hearings, the judge has chastised the former president’s lawyer, Todd Blanche, for not answering questions. When Mr. Blanche accused prosecutors of wrongdoing, Justice Merchan upbraided him.
“You are literally accusing the Manhattan D.A.’s office and the people assigned to this case of prosecutorial misconduct and trying to make me complicit in it,” Justice Merchan said.
During Mr. Trump’s trial, Justice Merchan will be in charge of keeping order in the courtroom and ruling on objections made by both sides, but a jury will decide whether Mr. Trump is guilty.
The trial, which could last two months as a parade of former aides and allies takes the stand against him, will dominate Justice Merchan’s calendar this spring, with testimony planned for every weekday but Wednesday. On off-days, he will continue to preside over Mental Health Court.
The program is for defendants charged with felonies and diagnosed with a serious mental illness. People who are accepted enter a guilty plea and then begin a period of treatment and judicial supervision. Those who complete the program successfully can have their charges reduced or dismissed.
On a recent Wednesday, Justice Merchan recognized the last court appearance of the man who, according to his lawyer, had been “saved” by medication.
“It’s always been a pleasure having you here,” Justice Merchan told the man, who was in his early 30s and had been charged with assault. “I’m just very confident you’re going to do well.”
Justice Merchan showed particular interest in the relationship between another defendant and his child, and praised him for his dedication.
“You want to do better by your daughter,” Justice Merchan said. “I’m sure she’s going to appreciate that.”
Maggie Haberman contributed reporting. Susan C. Beachy contributed research.