A police officer who works in a serious crash unit is under investigation for alleged drink-driving after he was reported for backing into a parked car.

The Herald understands the man works in Greater Auckland and blew 1100mcg - nearly three times the legal limit of 400mcg - when breath-tested two weekends ago.

Police are now waiting for the results of a blood test, which can take several weeks to arrive.

Police sources say the officer reversed into a stationary car in a North Shore car park, believed to be at a fast-food restaurant, and drove off.

Witnesses reported him to police and he was pulled over.

It is understood the officer has taken voluntary leave and will not be stood down unless the blood test yields evidence for a prosecution.

The officer could not be reached for comment.

The relieving area commander for North Shore police, Inspector Vitale Lafaele, refused yesterday to confirm the alleged drink-driving incident, citing sections of the Official Information Act involving privacy and a person's right to a fair trial.

The serious crash investigator is not the first police officer to get into trouble with the law over alleged drink-driving.

Constable Matt Hooper was pulled over by colleagues and breath-tested on Union St in central Auckland in December 2008.

But he avoided taking an evidential blood test at the station. It is understood he asked officers if he could go to the toilet.

He emerged with a head injury and was taken to hospital.

The Land Transport Act says blood taken in hospital for alcohol testing can be used in court only if the suspect is in hospital because of a car accident.

Hooper has since pleaded guilty to attempting to pervert the course of justice and been sentenced to 100 hours of community work.

Auckland police spokeswoman Noreen Hegarty said yesterday that he had been stood down pending the outcome of a "code of conduct process".

Two days after Hooper was tested, Superintendent Graham Thomas, a former police national prosecutions manager, refused a breath test in Wellington.

Last March, it was revealed that he had been cleared by an internal investigation but then took sick leave.

The Commissioner of Police, Howard Broad, said at the time that Mr Thomas was legally allowed to refuse the breath test, but as a senior officer was expected to take it voluntarily.