Inspector Turepu Keenan was seen texting while driving a police patrol car.
A senior policeman caught on camera using a mobile phone as he drove along a central Auckland street is now under investigation.
Last month the Herald published a photo of Inspector Turepu Keenan holding a cellphone while driving a police patrol car in the central city.
The photograph was taken by another motorist, disturbed at seeing what he described as Mr Keenan "constantly looking down" at his phone while he drove.
After being alerted to the photograph, police said Mr Keenan would be spoken to by his supervisor and given a chance to explain.
Spokeswoman Noreen Hegarty confirmed yesterday that police bosses were now taking further action.
"An internal investigation has been initiated into the activities of Mr Keenan, who was photographed holding a mobile phone while operating a police patrol vehicle."
It is illegal to operate a cellphone while driving a car, unless it is connected to a hands-free device.
Police are exempt from that law if they are using their phone in the execution of their duties.
Another senior officer said all police cars had been fitted with hands-free equipment "well before" cellphone legislation changed in 2009.
He said officers were told in no uncertain terms not to be seen using phones while driving. "If we do need to use it, we've been told to pull over and stop."