In the recent decision of Commonwealth v. Joseph J. Canty, the Massachusetts Supreme Judicial Court ruled that in cases where a defendant is charged with Operating Under the Influence of Alcohol, a police officer may not offer an opinion at trial as to whether the driver’s ability was diminished by the consumption of alcohol or that he was probably impaired by the consumption of alcohol.
In this case, the defendant was pulled over for erratic driving. The police officer testified at trial that the defendant breath smelled of alcohol and that he noticed his eyes were bloodshot. The officer also testified that the defendant admitted to having consumed four beer a few hours earlier. After failing several field sobriety tests, the defendant was arrested.
With this background, the police officer offered the opinion at trial that the defendant’s ability to safely operate the vehicle was diminished and that he was probably impaired.