The Government has confirmed that Paula Rebstock was paid $209,000 for her work on a report into who leaked documents to the Labour Party on restructuring at the Ministry of Foreign Affairs and Trade in 2012.
The report found the source was most likely a temporary State Services Commission staff member who used to work for Labour.
The total cost of the inquiry was $513,000 including legal costs from challenges to stop the commission from releasing the name of the individual.
Labour's State Services spokesperson Maryan Street says State Services Commissioner Iain Rennie did not allow natural justice to take place with what she calls a flawed report.
"He should have addressed those questions. At the very least natural justice should have been served but he sought to bury it at Christmas."
Ms Street says a review of state services is needed to make sure any government doesn't just buy the advice it wants.
The report of the 18-month inquiry was released late last year.