If you’re a lawyer, you have probably heard about Geoffrey Palmer and Andrew Butler’s proposal that New Zealand adopt a written constitution. Lately it seems to have come through all of the legal industry magazines that (both electronically and in real life) fly across my desk. That might not be surprising – Geoffrey and Andrew have written a book about their idea, and they are looking to sell a few copies.

If you are not a lawyer, or are not generally interested in legal things, I don’t know if you would have heard about the proposal. If this is the first time you have heard about it, or you have heard about it in passing before, you might think that adopting a written constitution is a good idea. You might think that because you have heard of Geoffrey Palmer, and understand that he knows a thing or two about constitutional issues. If he thinks it’s a good idea, why would adopting a written constitution be a bad thing?

I haven’t read the book (although I will when I get an opportunity). I don’t know if a new, written constitution will make our legal and political system work better. It might, although I suspect that will depend on what sort of written constitution we might adopt rather than the simple fact of having a written constitution. But I think there are important reasons to be sceptical about the claim that we need to engage in this kind of major constitutional change. In this post I’d like to set out some of my key reasons for holding this view.

My first reason is that our current constitutional system works well. It could be improved, sure, and we should strive to make sure it always represents the best possible reflection of our political values. But even as it is it delivers good constitutional outcomes most of the time, and that’s actually about all you can ask from any constitutional system. There is no acute problem for us to fix, and so a written constitution falls into that old policy trap of being a clear solution to a less‑than‑clear problem.

My second reason is that our constitution is relatively easy to improve to address the more chronic issues or specific shortcomings that we can identify. Precisely because our constitution is unwritten is it flexible enough to adapt to the new and inventive ways that politicians will try and use (and potentially abuse) their temporary power. Written constitutions tend towards ossification, which can mean that politicians have scope to outflank strong constitutional protections. Unwritten constitutions are, generally, better at adapting with the creative use of political power so the chances of their being a gap is much less likely.

My third reason is that virtually all of our constitution is already written down, and therefore accessible. It is true that there are multiple sources of the constitution, and they are not always in the same place. Ordinary New Zealand’s can struggle to understand constitutional nuance, but we should think carefully about the reasons for this. I would guess that it has less to do with where constitutional principles are found and more to do with the fact that constitutional issues are difficult by their nature. What we need is better civics education across the board in New Zealand. It is that education that makes the constitution accessible – not being written all in one place.

My fourth reason is that New Zealand has one of the most modern, fit‑for‑purpose constitutions in the world. Yes, we are an outlier in the sense that almost every other developed nation has a written constitution. But most of those constitutions have aged terribly. The Second Amendment to the United States Constitution is the most famous example. The ‘right to bear arms’ was a product of its time and has no real place in modern America. And yet, it is still invoked and argued over constantly. A minimalist, flexible, dynamic, democracy‑centric constitution that still finds room to recognise important values is what every country should strive for. And we already have it.

My fifth reason is that our unwritten constitution appropriately deals with human rights. Many advocates of a written constitution suggest that it will offer greater protection for human rights, citing their favourite specific examples where Parliament or the courts have failed to give sufficient protection in the past. I have my own examples, and on some of these important issues we could certainly do better. But I think offering these examples often misses the point. Our current arrangements have the advantage that all branches of government are bound to consider human rights and give them positive expression. Written constitutions tend towards a ‘set and forget’ mentality, where rights are treated as hard limits on political power rather than the values that animate that power. While protection might be stronger under a written constitution where it applies, we risk adopting a system where politicians can say “It’s not illegal, so I can do it and you can’t complain”. The system we have at the moment says to politicians “It might not be illegal, but it could still be unconstitutional so be very careful”. I know which system I prefer.

As I said, I don’t know which system will ultimately be better. I do consider, however, that the burden on those advocating change is high. I hope we can have a real debate about these issues and not get lost in a shiny new idea proposed by a former Prime Minister.