Rikki Craig Gerbich, 39, pleaded guilty to drink driving in the ACT on September 7. It was Gerbich's first offence.

Special Magistrate Margaret Hunter said what Gerbich had done was "foolish" and that the level of his reading worried her. She did not record a conviction or impose a penalty.

It is understood Gerbich was reprimanded by the Queanbeyan police force for his actions.

Special Magistrate Hunter said he had suffered professionally and could extend a leniency despite the blood alcohol level.

She added, "this will be the only chance you ever get".

Gerbich's reading of 0.1 qualifies as a level three offence which usually carries a minimum three-month disqualification period and a fine of up to $1400.

The court heard police became aware of Gerbich when he was stopped at traffic lights around 11pm at the intersection of Cowper Street and Limestone Avenue before he accelerated heavily once the light turned green.

ACT Police officers pulled Gerbich over and conducted a roadside breath test which was returned positive. Police later administered a test at the police station where Gerbich registered a reading of 0.1.

It is alleged Gerbich told officers he had driven from Woden to Ainslie after drinking five schooners.

Gerbich's defence lawyer told the court his client held a "position of great responsibility in Queanbeyan" and that he is married with a young child.

A spokesperson for NSW Police said an internal inquiry into Gerbich's actions was ongoing.

"The officer was the subject of immediate managerial action at time of his charging," the spokesperson said.

"The nature of this action is a private matter between the subject officer and his commander.

"As the criminal proceedings have been finalised, an internal investigation has begun into the 7 September 2017 incident."