Prostitution has been legal in New Zealand since 2003.
The officer had taken up prostitution because of financial difficulties
But senior police now found out the nefarious nature of her second job.
Law and order spokesman for the New Zealand First political party, Ron Mark, said organised criminals still ran the brothels and the officer would have been vulnerable to extortion.
"I know a hell of a lot of police officers who struggle with the cost of living in Auckland but they don't all rush out and become prostitutes," Mr Mark said.