Sticking to a deal
Such a policy is sometimes defended on the grounds that the treaty was made so long ago that it is no longer relevant. Since the circumstances of the mid-19th century are so different to those of today how can a document from then matter to us today?
This thought is sometimes reinforced by pointing out that people today are not obligated to make up for wrongs committed by their ancestors. If my great-grandfather insulted your great-grandfather, I do not owe you an apology. So how can it matter to New Zealanders today that the treaty was not adhered to after it was signed?
This line of argument is mistaken but the response often given to it by defenders of the treaty is equally mistaken. That response is to say that the treaty somehow embodies principles for biculturalism that are still relevant today for regulating interaction between Maori and Pakeha.
This is open to the criticisms that it is far from clear what the principles embodied in the treaty are, that figuring out what they are involves much creative interpretation, and that the result will be confusion and judges having too much power.
And these, of course, are precisely the problems that New Zealand First's policy is intended to address. Even if all these difficulties could be overcome, there is still a further problem with the response: if these are good principles for Maori-Pakeha relations then what does it matter whether they are embodied in a 165-year-old treaty or not? Good principles are good principles, so even if the treaty had never occurred the principles should be applied anyway. So what relevance is the treaty?
In contrast to this principle-based answer, a better response to criticisms of the treaty is to make a contract- based answer. Contracts are not merely legal arrangements, they are moral ones too. If I suddenly found myself on another planet with another being whom I did not share any legal system with, it would still possible for us to agree to help each other out and this agreement would create rights and obligations for both of us. Parties to a contract are morally bound to the terms of the contract.
Contracts also bind over time and as circumstances change. If two parties agree to exchange resources several years from now, it is no good if, when the time comes, one of the parties says "but that was several years ago – what does it matter today"?
Part of the point of agreements is that they enable people to make arrangements that persist over time.
Similarly for changed circumstances. If I agreed to give you a lift in my car I ought to do so even if something else I'd rather do instead has arisen in the meantime.
Associations can also be parties to contracts. A Doctor Who appreciation society might make an agreement with a Star Trek fan club to support each other so that a low-point of popularity for Star Trek during a Doctor Who revival, or vice versa, need not spell doom for either. This agreement remains binding even when one side perceives that it is shouldering a greater burden than the other.
The crucial point is that the agreement remains even though the individual members of the clubs change. This then is the relevance of the treaty today. It is an agreement between several associations to establish a common authority while at the same time limiting the power of that authority. Since these associations persist over time, members of those associations today should keep to the terms of the agreement.