An off-duty Edmonton police officer who was caught driving with alcohol in her blood in Saskatchewan was able to walk out of court without a criminal record.

Sgt. Cheryl Wallin had open alcohol in her SUV and a blood alcohol level that was twice the legal limit — but she left a Humboldt courtroom with an absolute discharge.

The incident took place in July, 2010. While off duty, Wallin was pulled over by RCMP on the highway outside Lanigan, Sask., according to records recently obtained by CBC News.

Other drivers had reported an SUV swerving across lanes and onto the shoulder near the town, which is about 125 kilometres east of Saskatoon.

Wallin, who's spent 23 years on the Edmonton force and has 15 awards and commendations, was charged with impaired driving.

Last year, she went to court in Humboldt.

There, she pleaded guilty to a lesser charge of dangerous driving and was given an absolute discharge, which can leave an accused person without a criminal record.

CBC asked the Saskatchewan Justice Ministry why Wallin was not tried for impaired driving.

On Friday, the director of prosecutions for the ministry, Lane Wiegers, said Crown lawyers did not believe they could win the case on the more serious charge relating to the blood alcohol content readings.

"The admissible evidence has to support conviction," Wiegers explained. "And there was a question as to whether or not the readings could be admissible evidence, and a very large question at the end of the day."

Meanwhile, Wallin's actions also resulted in internal discipline under the Alberta Police Act.

She pleaded guilty to discreditable conduct under the act and was suspended without pay for two weeks.