Few of the recommendations of a commission of inquiry into police conduct, concluded five years ago, have been fully implemented.
In 2007, the commission of inquiry - led by Dame Margaret Bazley - recommended wide changes to the police's handling of sexual assault complaints and organisational culture of the police, following
Louise Nicholas's accusations against police and the jailing of officers for raping a woman in Bay of Plenty in 1989.
The Government asked the Auditor-General to monitor the police's progress for a decade, and on Thursday the Deputy Auditor-General, Phillippa Smith, presented her third report.
It describes progress as mixed, saying leadership challenges remain and most of the commission's 47 recommendations are yet to be finished.
Ms Smith says progress on adult sexual assault investigation is relatively poor and that risks eroding the public's trust in police.
Acting Police Commissioner Viv Rickard says they have made huge progress in some areas, particularly around enforcing the Code of Conduct for police officers, but still have work to do.
Mr Rickard says he accepts the finding that more focus is needed on sexual assault investigations.
He says more than 1200 of the police's approximately 1500 investigative staff have received specialist sexual assault training, and the training of the others will be completed by the end of the year.
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