PORTLAND – The state supreme court ruled Wednesday that evidence obtained from the man behind the wheel of a vehicle parked in a University of Maine parking lot was seized illegally and cannot be used to prosecute him for drunken driving.

In what they acknowledged was “an admittedly close case,” the justices agreed that the campus police officer who rapped on Joshua Patterson’s side window was ordering him to roll the window down in what constituted a seizure under the Fourth Amendment.

Because Patterson and his passenger had remained in the car and had the engine running for at least five minutes on a cold January night in 2004, Sgt. Robert Norman suspected they may have been drinking alcohol or using drugs.

After Norman tapped on the window and told the driver to roll it down, Patterson opened the door, at which time Norman smelled cigarette smoke and alcohol. Patterson was charged with operating under the influence and driving after his license was suspended.

A District Court judge granted Patterson’s suppression motion on grounds that there was no “articulable suspicion” for the seizure, prompting the state’s appeal.

The state argued that because Patterson was not detained or stopped, his Fourth Amendment rights were not violated.

The Supreme Judicial Court disagreed, saying a seizure occurred because a reasonable person in Patterson’s position would not feel at liberty to disobey the officer’s order.

Penobscot County District Attorney Christopher Almy contrasted the decision with the court’s earlier finding that two Brewer police officers did not “seize” a motorist when they held out their badges, approached a parked vehicle but said nothing.

“How do you reconcile those two decisions?” the prosecutor wondered.

The court indicated that language or tone of voice used by Norman when he said, “Please roll down the window” could be the deciding factor.

“The officer may tap on the window and perhaps even open the door if the occupant is asleep. A request that the suspect open the door or roll down the window would seem equally permissible, but the same would not be true of an order that he do so,” the ruling stated.

Seth Harrow, the Bangor attorney who represented Patterson before the Law Court, said the supreme court realized the trial judge was in the best position to recognize that when an officer approached a college student’s car and told him to roll down the window, “this was in fact a command and not a request that he could ignore.”

Almy said he has not decided whether to move forward with the case against Patterson in light of the court’s ruling. “We are exploring our options,” he said.

Patterson’s attorney maintained that without evidence of alcohol use, the prosecution did not have much of a case.

Harrow also suggested that the decision had ramifications that could go beyond the charges against Patterson.

“It gives a lot more privacy to individuals sitting in their car and indicates to the police that they need to have some reasonable articulable suspicion – not merely ask them to roll down their windows so they can look in,” he said.