The Commissioner for Public Administration, Andrew Kefford, has confirmed an investigation was conducted by the Chief Minister and Treasury Directorate and that the disclosed information was wrong in a material way.

A public interest disclosure (PID) was lodged via MLA Shane Rattenbury in March 2013 and it was then forwarded to the commissioner.

It alleged the Labor Cabinet in the ACT Legislative Assembly had illegally received Treasury data showing how much each club in the territory paid in gaming tax.

This was allegedly during changes to gaming tax legislation in the period of 2004 and 2005 and the person who made the disclosure also alleged the information was used to benefit clubs which donated to Labor.

"In this case, the allegations made were based on an incorrect interpretation of the application of the Tax Administration Act," a response from the commissioner's office said.

ClubsACT chief executive Jeff House said he was unaware of the allegations, probably because these disclosures were supposed to remain highly confidential and that any public official disclosing information regarding PIDs was committing an offence.

"The nature of the taxation regime means it is virtually impossible to make changes to gaming taxes that favour individual clubs," Mr House said.

"My recollection of the tax changes imposed in 2004-05 was an across-the-board 2 per cent increase in the prevailing rates of tax for all tax paying clubs.

"Notwithstanding the allegation contained in the PID, no changes that I’m aware of were actually made to gaming tax which ultimately favoured particular clubs over others regardless of what may have been discussed in Cabinet."