The Privacy Commissioner says urgently-needed changes have not been included in government proposals to rewrite the Privacy Act.
The Government has announced the move eight months after the Law Commission completed its landmark review of privacy laws.
The Law Commission made 149 recommendations, but the Government has not yet moved on one of the key suggestions - increasing the Privacy Commissioner's investigative powers.
Commissioner Marie Shroff wants the scope to issue compliance notices and demand information-handling audits across the public and private sectors.
Ms Shroff says the change is urgent because it is difficult for her to respond to complaints at present - particularly about offensive material online.
But Justice Minister Judith Collins says giving Ms Shroff greater power of enforcement is an extremely complicated matter.
The Government is considering the idea and will not be rushed into a knee-jerk response, she says.