AGW law: New Zealand judgement day

Secondly, at paragraph 80, Venning J. elaborates on the issue of "officially recognised scientific opinion". Venning J. recognises NIWA's expert opinion that in respect of temperature adjusting and climate matters generally, there is no one "immutable" standard and indeed could not be.

NIWA's adjustments of temperature are, therefore, essentially subjective in nature, and like the definition of "excellence" to which the Trust claimed was the standard to which NIWA should be held accountable, not "readily susceptible to judicial assessment" [paragraph 74]. What the courts will do, as Venning J's judgement shows, is give considerable discretion to CRIs in their preparation of temperature networks and trends by adjusting raw data.

This discretion extends to subjective aspects of temperature adjustment where the institution can choose what method to adjust temperature data regardless of other methods and criteria; and in matters of fact where the institution has used or not used a method of adjustment of temperature data the institution is the preferred authority for concluding the fact of what it has done. On this basis the AGW science has been judicially settled.

New Zealand case law is not binding on other Commonwealth jurisdictions like Australia, but still persuasive.

In Australia the Bureau of Meteorology [BOM] compiles the Australian temperature network in a similar fashion to NIWA, by adjusting raw data. BOM has just replaced its old High Quality temperature network [HQ] with a new network, ACORN. BOM did this because it recognised problems with the HQ network which possibly made it inaccurate. ACORN has supposedly rectified those inaccuracies but has still produced a similar temperature trend to the HQ network. ACORN was peer reviewed by a panel of climate experts including NIWA representatives.

Questions were raised from outside BOM about the reliability of the HQ network. Questions are again being raised about the reliability of ACORN.

However, based on the New Zealand temperature case, any questions raised from outside the government scientific institution, BOM, especially from sources which the court does not recognise as being "officially recognised scientific opinion", is unlikely to have much credence given to it by judicial appraisal.