Stony Brook, NY – Jerry Diaz (24) Killed in DWI Collision on Nesconset Highway

Stony Brook, NY – Jerry Diaz (24) Killed in DWI Collision on Nesconset Highway. Long Island, NY.

Updated Jan 4, 2026
CRITICAL INCIDENT
Stony Brook
Town
Stony Brook
Reported
Source
News Sources

Map showing incident location at 40.7800, -73.3000 Incident location, Long Island

What Happened

A 24-year-old motorcyclist was killed early Saturday morning when an intoxicated driver turned into his path at a Stony Brook intersection, according to Suffolk County Police. Jerry Diaz of Nesconset died in the collision that occurred at approximately 12:22 a.m. on January 3, 2026, at the intersection of Nesconset Highway (Route 347) and New Moriches Road.

Police say Diaz was operating a 2022 Honda CRF450RL motorcycle westbound on Nesconset Highway when 25-year-old Mark Anthony Giordano of St. James, driving a northbound 2017 GMC pickup truck, attempted to make a left-hand turn onto the westbound Nesconset Highway from New Moriches Road. Giordano entered the path of the motorcycle during the turn, resulting in what police described as a violent collision.

Diaz was pronounced dead at the scene by a physician assistant from the Office of the Suffolk County Medical Examiner. Giordano was not injured in the crash but was arrested at the scene and charged with Driving While Intoxicated (DWI), according to the Suffolk County Police Department.

Both vehicles involved in the fatal crash were impounded for safety checks. The investigation remains active and is being handled by the Suffolk County Police Major Case Unit.

Location & Road Context

The intersection of Nesconset Highway and New Moriches Road in Stony Brook is governed by strict right-of-way laws, particularly for left-hand turns. Under New York Vehicle and Traffic Law § 1141, drivers intending to turn left must yield the right of way to any vehicle approaching from the opposite direction that is close enough to constitute an immediate hazard.

The DWI charge against Giordano adds what legal experts call “negligence per se” to any potential civil proceedings, meaning the violation of the law itself serves as evidence of negligence. The Suffolk County Police Major Case Unit continues to investigate the circumstances surrounding the collision.

Broader Impact

The DWI charge in this fatal collision carries severe penalties under New York law, with potential consequences including license revocation, substantial fines, and possible prison time, particularly given the fatality involved. The victim’s family may also pursue wrongful death claims, with the driver’s intoxication and failure to yield providing strong grounds for civil liability.

Disclaimer: Incident information on this page is compiled from public sources including police reports, traffic agencies, and news outlets. It is provided for informational purposes only and may not reflect the most current status of this incident. Do not rely on this information for legal, insurance, or emergency decisions. For emergencies, call 911.