Verdict comes after 7 days of testimony; accident victim was a retired Norwalk police officer.
Tree and landscaping company worker died 2 days after the Nov. 17, 2016 crash in Fitchville.
Prosecutors dismissed three felonies and a misdemeanor during a plea deal.
In separate case, a woman was charged in connection with escaping police custody.
Greenwald was charged with vehicular homicide and operating a vehicle while impaired.