Chris Dickinson has been placed on leave pending an investigation of conduct on a business trip.

EVERETT — A Snohomish County deputy prosecutor was arrested last month in Chelan after an alleged alcohol-fueled encounter with police. He recently was placed on administrative leave. An internal investigation is under way.

Chelan County sheriff’s deputies were called at 12:47 a.m. June 21. They were told that a man and woman appeared to be stealing a kayak on the south end of Lake Chelan.

They reportedly found Chris Dickinson, 55, of Arlington, in the kayak. His girlfriend, a 36-year-old Snohomish County probation counselor, allegedly was operating a motorboat nearby so drunk she could hardly stand. At one point, the deputies were worried the vessels would collide.

“She had fallen over and managed (to drive) from a partially lying position,” according to police documents obtained by The Wenatchee World, which first reported the allegations.

As the girlfriend began talking to deputies, Dickinson allegedly announced that he was a deputy prosecutor and told her not to cooperate.

“He began to demand that I acknowledge that he was a lawyer,” a sheriff’s deputy wrote.

The girlfriend was taken into custody, and a blood-alcohol test reportedly showed her at 0.26, more than three times the legal limit to operate a vehicle or vessel. Two hours later, one of the same deputies said he found Dickinson parked outside the police station in Chelan, apparently to pick up his girlfriend.

Dickinson was sitting in the driver’s seat of his girlfriend’s Chevrolet Equinox with the keys in the ignition, according to the reports. The vehicle was over the lines marking a spot reserved for deputy parking.

Around 3 a.m., Dickinson’s blood-alcohol test allegedly came back at 0.15. The legal limit is 0.08.

The pair were in Chelan for a conference of the Washington Association of Prosecuting Attorneys, which they had attended hours earlier. Other deputy prosecutors from Snohomish County participated in the conference, as well. The venue was less than four miles from the boating incident.

At the police station, Dickinson was arrested for investigation of being intoxicated while in control of a vehicle, public records show. The misdemeanor offense generally can be charged in cases when someone is above the legal blood-alcohol limit but wasn’t observed operating the car on the roadway. Dickinson allegedly told deputies that a friend drove him there and walked away, but he would not name the friend.

Dickinson appeared later that day in Chelan County district court while in jail custody, according to the records. He was released on personal recognizance, with arraignment set for July 24.

Snohomish County Prosecuting Attorney Mark Roe on Sunday told The Daily Herald he is waiting for the results of the internal investigation, which he expects early this week. He declined to discuss allegations of additional bad behavior until he has more facts.

“All I can say is an incident took place that left me disappointed and angry primarily at one person,” Roe said. “Even though a lot of the rumors are false, the truth is bad enough in my mind.”

Dickinson was placed on leave Tuesday, the day Roe returned to the office after being out of town. He has been with the prosecutor’s office for more than 20 years. His annual salary is about $149,000.

Earlier this year, a defense lawyer in Snohomish County juvenile court filed a motion to dismiss a case against her client. Dickinson was the prosecutor on the case. The defense alleged that justice was impossible because Dickinson and the assigned probation counselor began dating in November.

The same probation officer was the one taken into custody in Chelan on suspicion of boating under the influence, the marine equivalent of a DUI. She was cited, released and taken back to the place where she was staying. She also received tickets for two other boating-related infractions.

Rikki King: 425-339-3449; rking@heraldnet.com. Twitter: @rikkiking.