Mattituck man faces upgraded charges in fatal Riverhead crash

A Mattituck man who allegedly struck and killed a pedestrian in Riverhead while driving drunk last month now faces a top charge of aggravated vehicular homicide, according to online court records.

A grand jury on Tuesday indicted Matthew Nemschick, 54, on six separate felony charges following the Feb. 11 crash on West Main Street. Mr. Nemschick had originally been charged with felony driving while intoxicated after he was arrested at the scene by Riverhead Town police.

The crash left 38-year-old Alexander Lopez Guzman, who police said was homeless, dead.

Mr. Nemschick is also charged with one count of second-degree manslaughter and one count of first-degree vehicular manslaughter. Prosecutors said at Mr. Nemschick’s original arraignment that he had been convicted of DWI in 2018.

The indictment also includes a charge of tampering with physical evidence, two DWI charges and a misdemeanor charge of reckless driving.

Mr. Nemschick, who works as an electrician at Plum Island, is scheduled to be arraigned on the upgraded charges March 31 in Suffolk County Court before Judge Stephen Braslow. He is currently free after his bail was set at at $5,000 cash or $10,000 bond during his initial arraignment in Riverhead Town Justice Court.

The crash occurred near 953 W. Main St. shortly before 10 p.m. Police said at the time the victim was transported to Peconic Bay Medical Center, where he succumbed to his injuries.