The rights and duties in the articles of the Treaty could only become binding in New Zealand law if they were incorporated into New Zealand legislation.
As discussed in What is a treaty? a treaty has to be implemented by incorporation into the domestic law of a country.
https://thetreatyfacts.blogspot.com/p/what-is-treaty.html
Article 1 of the Treaty contained an agreement that the chiefs would cede sovereignty to the Crown. That agreement was implemented by the Crown's assertion of sovereignty over New Zealand just a few months after the signing of the Treaty at Waitangi. It is now accepted by the courts and the Waitangi Tribunal that the full sovereignty of New Zealand was vested in the Crown from that date. (See References at the bottom of this page.)
Article 2 of the Treaty contained an agreement that the Crown would guarantee the property rights of the chiefs, the tribes, and all the people of New Zealand. It was a transitional arrangement to protect existing property rights of Maori and settlers
The general property rights of all New Zealanders became protected under British legislation and common law once sovereignty was asserted by the Crown in 1840 and the new colonial government was established in 1841.
However the transitional rights in article 2 - protecting existing rights at the date of the Treaty - have never been incorporated into New Zealand law and are unenforceable in the courts.
However, claims for breaches of those rights were finally made available under the Treaty of Waitangi Act 1975, but those rights were based on breaches of the "principles of the Treaty" not on breaches of the Treaty itself.
Current outstanding claims will need to have an alternative remedy if legislation relating to the Waitangi Tribunal and the principles of the Treaty is repealed. Although prior claims were based on an overgenerous translation of taonga - which may not prevail today - there will have to be equity considerations between old and new claims because of any effect of the change in interpreting taonga.
The second part of article 2 relating to the chiefs' obligation to transfer land to the Crown is no longer relevant and of historic interest only.
Article 3 contains the Crown's promise to grant all New Zealanders the same rights as British subjects. This was effected with the vesting of sovereignty in the Crown in 1840 and the setting up of the colonial government in 1841. From that point on all New Zealanders became British subjects. Not because of the Treaty but because of the new constitution and British law.
Treaties are effectively "spent" once their various agreements have been implemented. The agreements in the three articles of the Treaty of Waitangi have all been incorporated into New Zealand law, except for the the guarantee of existing property rights for which a remedy of sorts is currently provided (for Maori only) through the informal Waitangi Tribunal claims process.
The result
The result is that the rights and obligations expressed in the Treaty itself have no further role to play either in New Zealand's constitution or in New Zealand law. This is typical of every treaty. Once agreement is reached on the future relations between the parties, they are then implemented and the terms of the treaty are satisfied (or ignored). After 283 years it can come as no surprise that the Treaty of Waitangi is just one of many historical treaties with only a symbolic significance.
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References
The full sovereignty of the Crown was asserted over New Zealand by Lieutenant–Governor Hobson’s proclamations and their gazetting in London in 1840.
This is accepted by experts in international law as legally vesting sovereignty in the Crown. It is also accepted by the courts of New Zealand. It is also a little known fact that In December 2022 in the Stage 2 report on the Te Raki claim the Waitangi Tribunal agreed with the courts that the sovereignty of New Zealand was lawfully asserted by the Crown in 1840.
For a full discussion of this issue see: https://thetreatyfacts.blogspot.com/p/hobsons-assertions-of-sovereignty.htmlhttps://thetreatyfacts.blogspot.com/p/legal-effects-of-assertion-of.html
https://thetreatyfacts.blogspot.com/p/the-sovereignty-solution.html
On 3 May 1841, New Zealand was established as a Crown colony in its own right, with Hobson as Governor. See: https://thetreatyfacts.blogspot.com/p/new-zealand-becomes-separate-british.html and https://thetreatyfacts.blogspot.com/p/legal-effect-of-erection-of-new-zealand.html
This was immediately followed in 1841 by the setting up of the machinery of government, the establishment of the Executive Council, the courts of law and a police force.
