Amanda Daniella Holton, 28, of Dryden Court, San Remo, pleaded guilty to mid-range drink-driving and was fined $500.

Her licence was suspended for the minimum allowable period of six months.

The court heard that Holton regularly drove for 3? hours from Taree, where she was stationed, to San Remo, after finishing a 12-hour shift.

"She may have felt fatigued as she does every week," solicitor Stuart Gray said.

Holton told police she had consumed about eight drinks at an Islington hotel from about 6pm on August 21.

Holton was stopped by police on the Pacific Highway at Belmont South about 7.35am on August 22.

She was estimated by police to be speeding.

Police smelled liquor and noted that her speech was slurred and eyes bloodshot. She returned a blood alcohol reading of 0.116.

Magistrate Michael Allen noted that Holton may have been anxious to return home to her eight-year-old child and said she was a well-respected serving police officer.

He told Holton he had to impose a conviction because of "the level of the reading and the very particular position you hold in the community".

"There's a need to send a very strong and clear message of deterrence," he said.

"[Drink driving] is too prevalent in the community."

Mr Gray said in court Holton might face internal police disciplinary proceedings.