Murder, kidnapping and drug trafficking convictions may be in doubt in the ACT after police revealed compliance issues with its phone intercepts.
Australian Federal Police said on Thursday it will review 13 years of phone location requests made by ACT Policing after finding compliance issues.
Police contact telcos to locate mobile phones, with requests only allowed for serious offences including murder, kidnapping, drug trafficking or terrorism.
Australia's police watchdog, the Commonwealth Ombudsman, is now set to investigate.
The AFP say compliance issues related to authorisations and record-keeping, with records of the requests later left out of reports to government.
Corrective actions had been taken, with the AFP saying location requests didn't give police access to metadata or personal communications.
A PwC Australia audit found compliance issues with the location requests program dating back to 2007, with an independent audit to be finalised by June.
ACT Policing are the local Canberra branch of the AFP.
Last year ACT Policing revealed they had illegally accessed citizens' metadata more than 3000 times in 2015, with data going on to be used in prosecutions.