Auckland Transport is refusing to release a report on the level of fare evasion on the city's rail network due to fears it could worsen the problem.
Some estimates suggest the region could be losing millions of dollars a year, but Auckland Transport won't disclose how it plans to tackle the matter.
The report was prepared at the request of Auckland Transport's new chairperson, Lester Levy, who is promising more openness at the agency.
Difficulties the agency faces include not having the power to fine commuters who don't pay, and the high cost of electronic ticket gates, currently installed at only three key stations.
The agency has previously said talk of fare evasion being around 10% could be either too high or too low.
Auckland Transport has refused to release the report on the grounds that it could encourage more evasion and prejudice any efforts to crack down on it.