Mr Hettig claimed he had powers to file court proceedings on the basis that firstly, the land was owned by the Kaiawhina Trust of which he was a beneficiary and secondly, he represented Ms Ruwhiu by way of enduring power of attorney- a legal document that sets out who can take care of personal and financial matters.
Mr Hettig later argued he had also been appointed an additional trustee of the trust.
ANZ lawyer Kalev Crossland argued the title of the property was registered under Ms Ruwhiu's name and there was no evidence the land was in fact held in trust.
He said all the ANZ's previous dealings had been with Ms Ruwhiu in her personal capacity and the bank had never been advised that she held the land on trust. Mr Hettig argued the sale and purchase agreement listed the trust as the purchaser.
In his decision released last week, Judge Miharo Armstrong found the trust was the purchaser of the land and Ms Ruwhiu held the property as trustee.
However, the judge said the bank was not advised about the trust and that all correspondence between ANZ and Ms Ruwhiu confirmed their understanding she held the property personally.
Judge Armstrong said while she owed fiduciary obligations to the trust in terms of the land, ANZ's mortgage was not affected by those duties.
He said if Mr Hettig sought to challenge the validity of ANZ's mortgage such proceedings should have been filed in the High Court.