Prosecutors say Cassandra Panetta ran a red light while high on methamphetamine, killing 55-year-old Steven Diamond and injuring two others.

MINEOLA, N.Y. – A Plainview woman has pleaded guilty in a deadly East Meadow crash that prosecutors say happened after she drove through a red light while under the influence of methamphetamine.

Cassandra Panetta, 41, pleaded guilty to second-degree manslaughter, second-degree assault and driving while ability impaired by drugs, according to the Nassau County District Attorney’s Office.

The August 2025 crash killed 55-year-old Steven Diamond, who prosecutors said was riding with friends on their way to spend the afternoon at the beach. Two other people in the vehicle were injured.

Prosecutors Say Panetta Never Braked Before Crash

The collision happened around 1 p.m. Aug. 10, 2025, as Panetta drove a 2021 Nissan Maxima along Carman Avenue toward her Plainview home.

Prosecutors said Panetta approached a red light at Carman Avenue and Salisbury Park Drive as another vehicle carrying three people made a left turn through a green light.

Panetta allegedly drove through the red light without braking and slammed into the rear driver’s side of the other vehicle.

The impact caused extensive damage.

Diamond, who was sitting in the back seat, was in cardiac arrest when paramedics arrived. He was taken to Nassau County Medical Center in East Meadow, where he was pronounced dead at 3:13 p.m.

The driver suffered a concussion, while the front-seat passenger sustained minor injuries. Panetta fractured her wrist.

Blood Test Found Methamphetamine and Amphetamine

Prosecutors said blood taken from Panetta at the hospital tested positive for methamphetamine and amphetamine.

“High on methamphetamine in the middle of the day, Cassandra Panetta got behind the wheel, plowed through a red light, and crashed into the car where Steven was riding in the back seat, taking his life in an instant,” District Attorney Anne Donnelly said.

Panetta was arrested Oct. 17, 2025, by detectives with the Nassau County Police Department Homicide Squad.

She entered her guilty plea before Judge Helene Gugerty.

Panetta Faces Up to 12 Years in Prison

Panetta is scheduled to return to court Dec. 8 for sentencing.

Prosecutors said she is expected to receive four to 12 years in prison. The Nassau County District Attorney’s Office has recommended a sentence of six to 12 years.

“Our hearts are with his family as they continue to grieve this immeasurable loss,” Donnelly said.

Senior Assistant District Attorney James Taglienti of the Vehicular Crimes Bureau is prosecuting the case. Panetta is represented by attorney Marc Gann.