As New Zealand was nominally part of New South Wales from 1787 and a dependency from 1814 to 1841 under the NSW Supreme Court Act, the situation has changed materially. NSW's 1828 Supreme Court Act contains authority to found all the relevant courts and use the same laws as in the UK; New Zealand was touched upon then. That legal system included rules of Chancery - 'equitable jurisdiction.' It gave NSW parity with all the other settlements or colonies. New Zealand's Supreme Court Ordinance was passed here on Dec 22, 1841, ready for a start on Feb. 1, 1842.
NSW not only created three Maori chiefs as public servants, Justices of the Peace, by ancient writ, but already had sued ships' captains if they had behaved cruelly to native people (1813). In 1814 an NZ magistrate was apointed. NSW took all financial responsibility here, funding courts for hearings about NZ, paying the sort of pro-consul, James Busby, the flags offered, passing of the Maori law in 1835, supervising protection of our Chiefs' contracts for Sale and Purchase UNTIL the Land Court moved from Sydney to Auckland.
The Principles of the Treaty were seen by NZ public servants as a right of landowners to sell land, or decline to sell.
NZ's Supreme Court in 1847 repeated 'Principles' known and used in the reign of Edward III of England. Also they were used across Europe similarly in coronation oaths : a named and authorised person as governor (or king), authority by treaty from the residents of a place and a charter to limit the incoming government. The reigning monarch of the society which was, or who were colonising or leasing a place, had to ensure land contracts were lawfully checked.
I believe NZ would be right to seek confirmation of early NSW actions, through the NSW and Australian courts, before creating a constitution with only a Treaty and no limiting Charter. The 1840 Charter was replaced in 1855, after special points were safeguarded in their own Ordinance. Th representative Parliament sat only in 1856, one year before Waikato chiefs and others asked for a new legal system; it was two years until the statutes could be written and passed. Chiefs received a mellowed '1689 Bill of Rights' regarding court process and tribal punishments. The rule for Witnesses or accusers came from the Old Testament.