Wearing his signature blue suit and red tie, Trump, 77, sat at the defense table while Justice Juan Merchan set limits on witnesses and evidence to be presented at trial and denied a motion by Trump's lawyers to have the judge recuse himself.
Trump's legal team has for months filed a flurry of legal motions to delay or derail the four criminal cases against him.
Trump, the 2024 Republican candidate for president, is required to attend the trial, which is expected to last through May. The selection of 12 jurors and six alternates from a pool of Manhattan residents is expected to take about a week, followed by witness testimony.
New York state prosecutors accuse him of falsifying records to cover up a $130,000 payment in the waning days of the 2016 presidential campaign to buy the silence of porn star Stormy Daniels about a 2006 sexual encounter she has said they had.
Trump has denied any such relationship. He pleaded not guilty last year to 34 counts of falsification of business records in the case brought by Manhattan District Attorney Alvin Bragg, a Democrat, in New York state court.
Police stood guard in front of the courthouse amid a maze of barricades, and helicopters shadowed the motorcade of black SUVs that ferried Trump from his Trump Tower apartment.
A handful of protesters, gathered in the plaza across the street, carried hand-painted signs reading “LOSER” and “convict Trump already.”
Though the case is regarded by some legal experts as the least consequential of the four criminal prosecutions he faces, it is the only one guaranteed to go to trial before the Nov. 5 election.
If convicted, Trump could still hold office but Reuters/Ipsos polling shows a guilty verdict could hobble his prospects.
The businessman-turned-politician, who served as president from 2017 to 2021, has used past court appearances to rally his supporters and claim he is being targeted by his political enemies.
Over the past year, Trump has criticized witnesses, court officials and relatives of those involved in the various legal cases - prompting Merchan and two other judges to impose limited gag orders against him.
In this case, Trump has unsuccessfully sought to force Merchan to step aside, arguing that he faces a conflict of interest because the judge's daughter has worked with Democratic politicians.
"This is an outrage," Trump said before entering the courtroom. "This is political persecution."
Bragg has argued that the case concerns an unlawful scheme to corrupt the 2016 election by burying a scandalous story that would have harmed Trump's campaign. Trump's lawyers have said the payment to Daniels did not amount to an illegal campaign contribution.
TABLOIDS AND A PLAYBOY PLAYMATE
Choosing a jury from a pool of people from heavily Democratic Manhattan could take several days, to be followed by opening statements and testimony from a parade of potentially riveting witnesses.
Those witnesses will include Daniels and Trump's former lawyer Michael Cohen, who has testified that he made the payments to buy her silence ahead of the 2016 election, in which Trump defeated Democrat Hillary Clinton.
David Pecker, the former head of the National Enquirer tabloid, will also testify that he ran stories in the tabloid to boost Trump's 2016 campaign, prosecutor Joshua Steinglass said.
Also due on the witness stand is Karen McDougal, a former nude model for Playboy magazine who prosecutors say was paid by the National Enquirer to keep quiet about an affair she says she had with Trump.
Merchan said he would not permit witnesses or prosecutors to tell the jury that the affair took place while Trump's wife Melania was pregnant with their child.
Trump has said he plans to testify in his own defense, a risky proposition that would open him up to probing cross-examination by prosecutors.
Merchan said he would not permit the jury to see other evidence of questionable sexual behavior by Trump, including a tape from the "Access Hollywood" TV show that included denigrating comments about a female host.
Trump is accused of falsely recording reimbursements to Cohen as monthly legal retainer fees in his New York-based real estate company's books. Falsifying business records in New York is a felony punishable by up to four years in prison, though many defendants convicted of that charge have been sentenced to fines or probation.
Trump's defense has argued that his payments to Cohen in 2017, while he was president, were for legal services. Trump has called Cohen a "serial liar" and his lawyers are expected to attack his credibility at trial. Cohen pleaded guilty in 2018 to violating campaign finance law, though the federal prosecutors who brought that case did not charge Trump.
