Police AI: Investigator uploads 350,000 lines of audio in risky workaround

Police investigators misused artificial intelligence (AI) translation tools numerous times in seriously risky ways, offical documents show.One investigator put 350,000 lines of Chinese audio data into Google Translate, an unsecured platform for police.The breaches came after initial success using the Whisper AI system to translate Chinese language phone interceptions collected in the investigation into the body found in a bag in Gulf Harbour in July 2024.This turned into a six-month test, but officers ignored a ban on using the AI to transcribe English audio, so use was discontinued after the test.The documents show investigators were under so much pressure, they began taking evidence home to process it on personal devices or upload it to unsecured services such as Google Translate.This risked "exposing confidential information", said a police report.The breaches pushed police to re-introduce Whisper AI a year ago. It is not clear how its use is being audited.Ten hours versus 750 hoursPolice have promised to be careful and transparent about introducing new high-tech crime-fighting tools.Internally, they say they are keeping the public informed "to the greatest extent possible". They declined an interview request from RNZ on this story.The 2024 Auckland cult investigation into the killing of Shulai Wang - dubbed Operation Parade - seized on Whisper to help officers who felt they had to act quickly, according to hundreds of pages of police emails and reports newly released to RNZ under the Official Information Act."The driver for this is that the investigation have advised there is now a significantly elevated flight risk of a number of targets," an email read.Officers had intercepted calls and had 250 hours of audio from more than 2500 files in Mandarin Chinese."The investigation has interpreters, but their time is limited."It took Whisper 10 hours to do what would have taken a person about 750 hours and $50,000 to do. It helped pin down which conversations and messages, or parts of them, to focus on. All evidence had to be validated later by qualified human translators.After this, automated translation began to spread to other teams.But police staff who did transcriptions heard about it and became alarmed about what it meant for their jobs.A formal test of Whisper AI was set up, with controls, such as not using it to transcribe English audio, or on Māori or Pacific languages.Breaking the rulesSix months later, an evaluation found officers had broken the no-English rule many times.In one case, Waikato investigators not only broke that rule but used AI to generate a document for disclosure in legal proceedings. Not using AI for evidentiary purposes is a theme in all the papers.Police encountered trouble controlling its use. "The ongoing compliance is beyond current resourcing," the High Tech Crime Group warned early on.The breaches posed serious security and privacy risks, Intercept and Technology Operations manager Detective Inspector Stu Mills said later in evaluating the test.But he also said they were "unfortunate but not unexpected" due to the pressure on investigators.Mills warned that unless police adopted a permanent approved AI tool, investigators would turn to unsecured translation platforms.Despite this, Whisper was dropped in March 2025, except in a few one-off cases that needed three lots of signoff. Several of those cases were to transcribe English language from hundreds of prison phonecalls.'Running for years damaging the police's reputation'The papers show investigators used AI anyway.In one case, they scraped cellphones for WeChat threads using Cellebrite, a phone-cracking tool invented by ex-Israeli intelligence operatives. Police use of Cellebrite has been well publicised, while WeChat is China's leading messaging and social media service.They then put 350,000 lines of the Chinese audio on to Google Translate."This needs to be done to enable us to grade this in a timely manner and determine what's important to the investigation to be able to be passed to the translators for translation and transcribing of the audio files," they emailed."Without being to grade the data in a timely manner this investigation will have the potential of running for years damaging the police's reputation (trust and confidence, etc)."The investigation is not named, but was likely a financial one in 2025.'We are exhausted'The on-again-off-again access to Whisper had tech and investigation leaders at odds."Man what a process trying to get this approved!" wrote a Western Bay of Plenty detective constable in July 2025.A High Tech Crime Group manager protested about "constant change" in the rules overseen by the Tech Assurance group. "We are exhausted."Mills told tech leaders debating what to do: "The lack of a secure, approved solution has driven staff toward these risky workarounds, highlighting the urgent need for a trusted in house capability."They worked to streamline access to Whisper, then to get it re-adopted.By October last year, the AI translator was being incorporated into the other tech they already used - Cellebrite.The papers shed little light about Whisper in the past 12 months, except that it appeared to be widely available to use. It remained unclear how usage was audited or the rules overseen.