So what would it have cost? How much is "too much" for this government to pay for transparency? After a year-long battle, the Ministry has finally released all the documents unredacted: the draft cabinet paper, and rejected budget bid (other documents and redacted versions can be seen here). The budget bid makes it clear that a full review by the Ministry of Justice would have cost less than $4 million over four years - $1 million a year. Which is pocket change on a government scale - but apparently too much for Labour to pay. Which shows you just how little they value being "the most open, most transparent Government that New Zealand has ever had"...
(That cost is for an internal review by MoJ. As I've said before, they're probably not the best people to do it, as they lack both independence and credibility on the topic. By way of comparison, the Law Commission's 2012 review cost something like $2.6 million over three years (Their 2010 Statement of Intent says they had a total budget for advice of $3.5 million, with an expectation of 3-5 reports to parliament each year). So, an independent, external review would be no more expensive, and possibly cheaper, even allowing for inflation. But then Kibblewhite wouldn't be able to strap the chicken...)
Its also worth noting that - as an unredacted email states - this was a confidence and supply issue, to meet the commitment in the Labour - Greens 2017 confidence and supply agreement to "Strengthen New Zealand’s democracy by increasing public participation, openness, and transparency around official information". But after dragging their feet on it for years, it got dumped the moment the political situation changes (unlike the promises made to NZ First around climate change, capital gains taxes, waka jumping etc, which are apparently fixed and immutable). So again, that tells us how much is "too much" for Labour to keep its promises: $1 million a year. Future cooperation partners should take this as a warning.