Former President Donald J. Trump attended a wake on Thursday honoring a New York City police officer who was killed in Queens during a traffic stop on Monday evening.

Officer Jonathan Diller, a three-year veteran of the New York Police Department, was killed after stopping a motorist in the Far Rockaway neighborhood just before 6 p.m. on Monday. He was 31 and the father of a 1-year-old.

Karoline Leavitt, the Trump campaign’s national press secretary, said earlier this week that Mr. Trump “is moved by the invitation to join N.Y.P.D. Officer Jonathan Diller’s family and colleagues as they deal with his senseless and tragic death.”

Mr. Trump’s appearance came less than three weeks before the start of jury selection in his criminal trial in Manhattan. He has been indicted on charges that he falsified business records to cover up hush-money payments to a porn star who was prepared to discuss a past affair with him during the 2016 presidential campaign.

It was unclear how Mr. Trump was connected to the Diller family. But the former president, who has been indicted in three other jurisdictions on a variety of criminal charges, has repeatedly appeared with police officers throughout his 2024 presidential campaign. Many officers seek to take photos with Mr. Trump at political stops after they have helped guard his motorcade.

His visit to Officer Diller’s services is likely to garner intense local media coverage ahead of April 15, when jury selection is set to begin in what may be the only trial that Mr. Trump faces before the general election in November.