Dr Ryan Malone is a former Cabinet Officer staffer and a public law commentator. He writes in the Dom Post on the Sky City deal:
Can the SkyCity agreement, and the resulting legislation, be considered a breach of our unwritten constitution? The argument of constitutional impropriety rests on three pillars. None are very persuasive.
The first is that the legislation will benefit just one person, in this case SkyCity. This, it is argued, is offensive to the rule of law because legislation should be of general application to everyone.
This is certainly true of criminal laws passed by Parliament. Here we are all equal before the law. Yet outside of this area, Parliament regularly makes laws that benefit a single individual or group. Private bills by their very definition change the law for the benefit of a particular person or company.
Similarly, local bills relate to specific regions. Parliament gave Wanganui District Council the power to ban gang patches in parts of the town. Not all local authorities were given this power – just Wanganui District Council.
Perhaps more importantly, government bills are commonly passed that benefit one individual or industry group to the exclusion of others. Thus, individual iwi receive compensation packages through statutes that implement Treaty of Waitangi settlements with the Crown.
So that is the first point dealt with.
The second argument as to why the deal is unconstitutional is that by amending the Gambling Act in exchange for building the convention centre, the Government is “selling” a dispensation from the Gambling Act. …
But what is clear is that parties in government always face difficult tradeoffs when making big policy decisions. In this case the National Government – still facing challenging economic conditions – considers that the pros of having a privately funded national convention centre outweigh the cons. Not everyone will agree with that assessment, and they will have the opportunity to express their views at the next election. But hard policy choices do not automatically equate with governments running roughshod over our constitution. …
It also changed the Overseas Investment Act regulations to ward off the Canadian Pension Board’s takeover bid for Auckland Airport. The fact that many people opposed those decisions did not make the resulting laws unconstitutional. They were simply political decisions taken by the government of the day. The Government’s deal with SkyCity is no different.
And the third point:
The third reason why the deal is supposedly unconstitutional is that it “binds” a future government. Under the terms of the agreement, SkyCity is entitled to compensation if key parts of it are overturned. But it is not unusual for governments to have their hands tied by earlier decisions of Cabinet or Parliament.
For example, the current Government must pay Tainui and Ngai Tahu additional settlement money because of relativity clauses inserted in legislation passed by Parliament in the 1990s. In any event, it will always remain open for a future Parliament to revoke the deal and specifically rule out compensation to SkyCity.
Our Parliament is free to enact laws that remove rights without compensation and has done so in the past. The Government’s agreement with SkyCity is not contrary to New Zealand’s constitutional system. Fundamentally it is a political issue, not a legal one.
And one announced prior to the last election.
For a different view, there is this opinion from Stephen Franks.