Donald Trump became the first former US president to stand trial in a criminal case on Monday when he appeared in a Manhattan court to face charges stemming from a hush-money payment to an adult star that could complicate his bid to win back the White House.

Wearing his signature blue suit and red tie, Trump, 77, sat expressionless at the defence table with his attorneys while photographers snapped his picture. Justice Juan Merchan, who is overseeing the trial, entered about half an hour later.

Trump 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.

Within minutes, Merchan denied Trump’s second bid to have the judge recuse himself from the case, on the basis that his daughter’s work for a political consulting firm with Democratic clients poses a conflict of interest.

New York state prosecutors accuse the former president of falsifying records to cover up a $130,000 payment in the waning days of the 2016 presidential campaign to buy the silence of adult film star Stormy Daniels about a 2006 sexual encounter she has said they had. Trump has denied any such relationship.

He pleaded not guilty 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 last year.

Police stood guard in front of the courthouse amid a maze of barricades, and helicopters shadowed the motorcade of black SUVs that ferried Trump, the Republican candidate in the 2024 White House race, 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 this case is regarded as the least consequential of the four criminal prosecutions he faces, some legal experts say it is the only one guaranteed to go to trial before the November 5 election.