Donald J. Trump is all but certain to become the first former American president to stand trial on criminal charges after a judge on Monday denied his effort to delay the proceeding and confirmed it would begin next month.
The trial, in which Mr. Trump will be accused of orchestrating the cover-up of a simmering sex scandal surrounding his 2016 presidential campaign, had originally been scheduled to start this week. But the judge, Juan M. Merchan, had pushed the start date to April 15 to allow Mr. Trump’s lawyers to review newly disclosed documents from a related federal investigation.
Mr. Trump’s lawyers had pushed for an even longer delay of 90 days and sought to have the case thrown out altogether. But in an hourlong hearing Monday, Justice Merchan slammed their arguments, rejecting them all.
In a particularly low moment for the defense team, the judge questioned the claims — and eventually, the résumé — of one of Mr. Trump’s lawyers as the former president looked on.
After a midmorning break, the judge returned to the courtroom, said that the former president had suffered no harm from the late disclosure of the documents and made the April 15 trial date final.
“Defendant has been given a reasonable amount of time,” the judge said crisply.
The ruling — coming nearly a year to the day after the Manhattan district attorney’s office obtained an indictment of Mr. Trump — makes it highly likely that the former president will go on trial next month even as three other criminal cases against him are mired in appeals and other delays.
