OUI in a Parked Car: The Operation Element in Massachusetts

By Attorney Joe Serpa | Georgetown University Law Center | 30 Years Massachusetts Criminal Defense

A common question follows an arrest that happens in a parked car. If the car never moved, how can the Commonwealth prove operating under the influence? Massachusetts defines operation broadly, and a 2025 decision of the Supreme Judicial Court confirms how far that definition extends. This post explains the operation element of an OUI charge and how the defense approaches it.

What Operation Means

Under G. L. c. 90, § 24, a person operates a motor vehicle when, in the vehicle, they intentionally do any act or make use of any mechanical or electrical agency that alone or in sequence will set in motion the motive power of the vehicle. Commonwealth v. Uski, 263 Mass. 22 (1928). The vehicle does not have to move. A vehicle may be operated while standing still, and the engine does not have to be running. Commonwealth v. Clarke, 254 Mass. 566 (1926), citing Commonwealth v. Henry, 229 Mass. 19 (1917). The definition covers a vehicle at rest because the danger the statute addresses includes an impaired person who may set a stationary vehicle in motion.

The Wurtzberger Decision

The Supreme Judicial Court applied this definition to a stationary vehicle in Commonwealth v. Wurtzberger, 496 Mass. 203 (2025). An impaired person sat in the driver’s seat of a van with the key turned far enough to power the radio, and the engine was not running. The driver’s side door was blocked by a tree. The court held that the evidence was sufficient to prove operation, because turning the key to engage the vehicle’s electrical power is an act that, alone or in sequence, will set the motive power in motion. The court explained that a person who takes that step and then remains in the driver’s seat continues to operate the vehicle, whether or not the person intends only to use the vehicle as a stationary platform.

What the Commonwealth Must Still Prove

Operation is one element, and it does not stand alone. The Commonwealth must also prove that the operation occurred on a public way, or in a place where the public has a right of access, and that the person was under the influence of alcohol or drugs or had a blood alcohol level of .08 or greater. The proof of operation is often circumstantial. The location of the vehicle, the position of the keys, the temperature of the engine, and the person’s own statements can each support an inference that the person operated the vehicle.

How the Defense Approaches Operation

Operation is frequently the contested element when the police find a driver parked, stopped on the shoulder, or asleep behind the wheel. The defense examines whether the evidence shows an intentional act to engage the vehicle rather than mere presence in it, whether another person may have driven, and whether the Commonwealth can prove operation on a public way. When the proof of operation is weak, the issue can support a motion for a required finding of not guilty. The same operation standard applies in other driving offenses, so the analysis carries over to related charges.

Attorney Serpa defends operating under the influence cases across the Massachusetts District Courts and the Boston Municipal Court. For a confidential consultation, call 617.936.0201, or read more about Massachusetts OUI defense.