Accused cop killer Guy Rivera faced a sea of blue as his trial proceedings began on Tuesday morning.

Opening statements were held in the case in Queens Criminal Court in Kew Gardens.

The Police Benevolent Association of the City of New York addressed reporters before filing into the courtroom.

 Last week, jury selection got underway.

Rivera is accused of fatally shooting Massapequa Park native, New York Police Detective Jonathan Diller, 31, on March 25, 2024.

According to investigators, Diller and other officers were conducting a traffic stop in Far Rockaway, Queens, just before 6 p.m. Prosecutors said they believed the two men in the car may have had a weapon on them and were planning to rob a nearby cell phone store.

Prosecutor Kenneth Zawistowski, Assistant Deputy Bureau Chief of the Homicide Bureau in the Queens District Attorney's Office, told jurors that Rivera "chose violence."

He said that before Diller lost consciousness, he used the last of his strength to pull the gun out of Rivera's hand and threw it to safety.

Zawistowski described what he said happened in the moments that lead up to the shooting. He said that Rivera, in a car, did not listen to officers' commands to roll down the window. He said Rivera was told, "Do not put your hands in your pocket." But he did, Zawistowski said, took out his gun, pointed it at Diller, and pulled the trigger.

Rivera's attorney, Erin Darcy, told jurors that the weapon's discharge was "unintentional." She said there is no evidence that Rivera intended to pull the trigger of the firearm and said there's no evidence that he aimed a gun at a member of law enforcement when the gun discharged.

Jurors watched police body cam footage of Diller on the ground after he'd been shot and the frantic attempts to save him.

Diller was rushed to the hospital, where he died.

Rivera was charged with murder, attempted murder and criminal possession of a weapon. He faces life in prison if convicted.

The driver of the car involved, Lindy Jones, was charged with weapons possession.

Both men have extensive criminal records, according to prosecutors.

Diller was buried on Long Island and left behind a wife and young son.

The trial continues Wednesday with more prosecution witnesses.