When Parliament passes a bill through its third reading and it is rubberstamped by the Governor-General, it's the law, right? Well, yes - and no. Every law in New Zealand has a commencement date. Some come into force immediately, some on a specified date (to allow alignment with the tax or calendar year, or for implementation to be finalised), and some on a date "to be appointed by the Governor-General by Order-in-Council". These latter ones can lead to problems.
According to this list [PDF] from the Parliamentary Counsel's Office, there are 43 laws which are at least partly waiting to be brought into force by such an order - some of them dating back to the 1980's. Some (e.g. the Corrections (Mothers with Babies) Amendment Act 2008) are waiting to be properly implemented. Some (e.g. the Nuclear-Test-Ban Act 1999, and parts of the Climate Change Response (Emissions Trading) Amendment Act 2008) are waiting for international agreements to come into force. But some have not been implemented because the government has not bothered to fund them, or in some cases has changed its mind about what it wants to do and now has no intention of implementing them. This is untidy. But its also constitutionally dubious. After all, Parliament has passed a law. The executive should therefore be implementing it. If they don't want to - if they change their mind or there is a change of government - then the appropriate response is to repeal that law, not to simply refuse to bring it into force.
As for the solution, I think that unless there is a good reason for such a contingency, such as a treaty, such clauses should have a default commencement date of e.g. two years in the future, unless brought into force earlier by Order. That way, the executive will have to dance to parliament's tune, rather than being allowed to effectively legislate by their own whim.
