Victoria’s Transport Ticketing Authority has fielded 113 requests from police for location data on users of the state's myki contactless ticketing system since 2009.
Of those, only eight were denied over the three-year period.
The ticketing system logs when users enter and exit trams, trains and buses. Users can register their cards — using their name and email — to safeguard their account balances if cards are lost.
Those with concession cards must register them, adding their identity for easier tracking by authorities.
Police issued 71 requests this year for the data, more than tripled the number of requests logged for 2011, according to The Age.
The written requests could be made without legal checks but police would be knocked back if they fell short of unnamed authority baseline standards.
The Australian Privacy Foundation told The Age the data should not be held within the cards.