The Ombudsman is investigating the government's refusal to publicly release the full legal advice on KiwiSaver funds investing in controversial weapons companies.
In September, Minister of Commerce Paul Goldsmith said he was withholding the advice to maintain professional privilege, and because it was not in the public interest to know the full details.
In August, RNZ revealed all nine default KiwiSaver providers had direct or indirect investments in companies that made nuclear weapons, cluster bombs or anti-personnel mines.
At the time, Mr Goldsmith said initial advice indicated New Zealand laws banning these weapons, or aiding the manufacture of them, might apply to KiwiSaver funds.
Chief Ombudsman Judge Peter Boshier said he has written to the minister asking him to provide a copy of the full legal advice as the first step of his investigation into the issue.
All nine default KiwiSaver providers have since dumped, or are in the process of dumping, their direct investments in such companies.
ANZ went a step further dumping its direct investments in tobacco companies also.
Several providers have also since switched their investments in global passive funds, which invested in such companies, to funds that excluded tobacco or weapons.