MOUNTLAKE TERRACE — A Mountlake Terrace police commander has been fired in connection with his recent arrest for drunken driving.

Don Duncan, 50, was on call the night of Jan. 31 when he was pulled over by a Washington State Patrol trooper. He reportedly tried to talk his way out of a DUI arrest and accused the trooper of being untruthful.

Duncan had been with the police department for nearly 18 years, and was a police commander for the past two years.

In the 14-page termination letter sent Thursday, Mountlake Terrace city administrator Arlene Fisher wrote that Duncan’s behavior showed “a complete absence of judgment” and reflected poorly on the police department.

Duncan’s attempts to justify what happened that night, including placing blame on his coworkers, were “feeble” and “unfathomable,” Fisher wrote.

On Jan. 31, Duncan reportedly was drinking with others at an Arlington-area restaurant until 1 the next morning. He then drove a friend to the Tulalip Resort Casino, where he stayed for a while before driving home toward Lake Stevens.

A trooper noticed Duncan’s car crossing the center line and that his headlights weren’t on, according to public records.

Duncan, who’d identified himself as a Mountlake Terrace police officer during the stop, submitted to field sobriety tests but declined to take a breath alcohol test.

The trooper happened to have a county district court prosecutor on a ride-along. A State Patrol sergeant also responded to assist with the arrest.

Both the prosecutor and the sergeant reported that Duncan appeared intoxicated.

Just after 3:15 a.m., hours after being arrested, Duncan took a breath test and reportedly blew a .055 and .058. The legal limit to drive in Washington is .08.

Duncan’s case was forwarded to prosecutors, and he was charged with drunken driving.

He was placed on leave from the police department during a separate, internal investigation.

The 259-page internal investigation determined that Duncan violated department policies related to on-duty and off-duty conduct, work performance and safety.

At a disciplinary meeting on April 22, Duncan gave the city a letter from his attorney saying that his expected termination was unjust and unwarranted, and that the internal investigation was flawed.

During the internal investigation, Duncan reportedly told officials he had not received proper training about being on-call as the command duty officer. In that position, he is expected to respond to any major incidents, such an officer-involved shooting or homicide, and assume a leadership role and be the face of the department.

The investigation found that Duncan allegedly had drunk alcohol on multiple occasions when he was on call as command.

The prosecutor who was on the State Patrol ride-along wrote that Duncan should have been “understanding, or gracious” about the position the trooper was in, instead of implying that the trooper was making a bad call by arresting him.

Duncan pleaded not guilty to the DUI charge and the case is pending trial, court records show.

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