LEWISTON – A Maine State Police trooper was startled to find that the driver of the car he pulled over was a 12-year-old boy.

Trooper Ricci Cote said the Chevrolet Avalanche SUV he spotted on North River Road in Greene at about 12:30 a.m. Saturday was moving erratically.

When he reached the driver’s side window, he was surprised to see a boy behind the steering wheel. The boy’s father sat in the front passenger seat. He told Cote he had made his son drive. The father said he had drunk too much and was on prescription drugs. He failed several field sobriety tests, and Cote arrested him.

“He was very remorseful and cooperative,” said Cote, who declined to identify the father.

A spokesman at the jail said Cote arrested Robert Haas, 34, of Greene and charged him with endangering the welfare of a minor and allowing the illegal operation of a motor vehicle Saturday in Greene.

The father’s fiancée came to the scene and picked up the boy. The vehicle was towed.

The father was taken to Androscoggin County Jail where he was booked and voluntarily took an Intoxilyzer test. His blood-alcohol level was recorded at 0.10 percent. The legal limit for driving is up to 0.08 percent.

The father said he had recently been awarded full custody of his son in court, but the boy’s mother said she shared custody.

Cote notified the Department of Health and Human Services, which, he said, planned to investigate.

He said he had no reason to believe the boy was in an unsafe environment.

“It’s poor judgment on (the father’s) part and fortunate I stopped them before something happened,” Cote said.