Montville ― Police have arrested a 51-year-old Stonington man on charges he caused a fatal crash that killed a motorcyclist last summer on Route 32.

James B. Grady of 538 Taugwonk Road is charged with negligent homicide with a motor vehicle and failure to yield right-of-way in the Aug. 19, 2023 crash that claimed the life of 36-year-old Michael F. Mariano of Waterford. Negligent homicide is a motor vehicle offense that carries a maximum sentence of three years in prison.

Montville police investigated the cause of the crash with aid from the Shoreline Accident Reconstruction Team and obtained a warrant for Grady’s arrest based on the findings of the investigation.

Police said Mariano was driving his motorcycle south on Route 32 when he was struck by a northbound vehicle driven by Grady that turned left into the path of Mariano’s motorcycle in the area of 1052 Norwich New London Turnpike. Mariano was pronounced dead at the scene of the crash.

Grady turned himself in to police on May 2 after learning of the warrant for his arrest. He is free on a written promise to appear in court. He is scheduled to appear May 14 in Norwich Superior Court.