Diller verdict: NYPD Commissioner Jessica Tisch says she's 'deeply disappointed' in shooter's murder acquittal

NYPD Commissioner Jessica Tisch said Thursday she was "deeply disappointed" in the jury verdict in which the man accused of killing NYPD Det. Jonathan Diller was cleared of the top murder charge, saying the decision was a "gut punch" to all her officers.

"I am deeply disappointed that the top murder charge didn’t result in a conviction," Tisch said during a news conference at 1 Police Plaza on the latest crime statistics. "Based on all the evidence presented at trial, I am convinced this was an act of intentional murder. ... The failure to convict on murder 1 landed like a gut punch to all members of the NYPD."

Although New York City Mayor Zohran Mamdani did not address criticism of verdict, he did talk about Diller's loss in the context of gun violence and the city's efforts to curb it.

"I know that the heinous killing of Det. Diller also weighs heavily today," the mayor said at the NYPD's downtown headquarters. "Many in this room knew him well. His loss still feels unfathomable. I am grateful for his service, and my heart is with his loved ones."

Tisch’s comments were part of a number of expressions of outrage by law enforcement officials and politicians about the verdict in the case of Guy Rivera in Queens State Supreme Court on Wednesday. The jury acquitted Rivera, 36, of intentional first-degree murder in Diller's death but convicted him of the lesser included offense of aggravated first-degree manslaughter, attempted first-degree murder of Diller’s partner and two weapons charges.

As a result of the convictions, Rivera, who has a prior felony conviction, faces a prison sentence of 90 years to life when he is sentenced April 27 by Queens Supreme Court Judge Michael Aloise.

After the verdict, Police Benevolent Association president Patrick Hendry expressed his own outrage.

"This was murder 1 against a New York City police officer, no doubt about it," he said.

Officers in the courthouse when the verdict was announced also privately expressed shock at the murder acquittal.

When the verdict was announced in the courtroom Wednesday, Diller’s widow, Stephanie Diller, of Massapequa Park, put her hands to her face and seemed distraught. Relatives near her tried to console her. Neither Stephanie Diller nor other family members commented when they left the courtroom.

Queens District Attorney Melinda Katz said her office respected the jury verdict and pointed out that Rivera still faces the rest of his life behind bars. She refrained from criticizing the jury.

In a statement released Wednesday, Nassau County Executive Bruce Blakeman said "our hearts go out to the Diller family on this very disappointing verdict."

Blakeman added that shooting and killing a law enforcement officer should be a capital offense. "The laws of ours state need to be amended so that legal loopholes do not frustrate the fullest prosecution and punishment of cop killers," said Blakeman, a gubernatorial candidate, referring to the absence of a viable death penalty law in New York State.

Tisch spoke about Diller and his sacrifice as a police officer at a news conference touting the last three-month crime statistics review alongside Mamdani.

According to the NYPD, the city reported the lowest number of homicides and shootings in the first quarter of 2026 than any such quarter in the history of modern recordkeeping. Major crimes were also down 5.3% citywide. Police also seized more than 1,000 illegal guns during the first three months of year.

NYPD Chief of Department Michael LiPetri said the gun-seizure activity symbolized the work Diller had been doing as part of a community response team seeking illegal firearms in Queens when he was shot dead on March 25, 2024.

By Anthony M. DeStefano

tony.destefano@newsday.comtonynewsday

Anthony M. DeStefano has been a reporter for Newsday since 1986 and covers law enforcement, criminal justice and legal affairs from its New York City offices.