The Police are being condemned for their treatment of protesters at Christchurch demonstrations against Chinese President Jiang Zemin.
A special Parliamentary inquiry into the protests, which followed last year's APEC summit, found police failed to uphold New Zealanders' right to protest.
Inquiry head Janet Mackey admits the protests did present a dilemma for the police, as they had to protect the dignity of a visiting president and uphold the rights of the protesters.
In the end, Ms Mackey says they traded off the rights of New Zealanders in order to keep peace with Chinese officials.
The inquiry also says police evidence given to it under oath was unconvincing and inaccurate.
Ms Mackey says crucial evidence - a video of the then Prime Minister Jenny Shipley talking to police - was not available to the committee because it was inadvertently wiped.
The inquiry has suggested a number of areas for improvement including clearer guidelines for police in controlling demonstrations against foreign dignitaries.