An action commenced for 265 dairy farmers who claimed that the NZDB and the LIC were commercially motivated when they introduced a new animal evaluation model in 1996*. The claim was particularly complex and alleged misleading and deceptive conduct in developing the new model and that the resultant product was defective. The case lasted several years and was partially funded by large American corporations. It ultimately failed before the Court of Appeal.
*Among other things, the animal evaluation model uses all NZ herd testing data to produce supposedly reliable information against which farmers can make appropriate culling and breeding decisions.

GCA acted for a large number of property owners in Queen Charlotte Sound who were adversely affected by the wave action caused upon the introduction of new ‘fast ferries’ between Picton and Wellington. Although a class action based on ‘nuisance’ was formed and the GCA lobbied government and achieved immediate Ministerial intervention. This led to the Marlborough District Council introducing appropriate restrictions which slowed the boats (and subsequently, one Ferry operator went out of business).

The claim arose principally from torture applied to nearly 300 children in Department of Social Welfare custody. All were state wards and a child psychologist systematically applied Electroconvulsive ‘treatment’ as a punishment regime, without any medical basis for doing so and without any pretense of following correct medical processes. A class action was brought against the Crown alleging breach of fiduciary duty and negligence. GCA represented 95 clients and recovered $6.5M and costs. The firm’s work also gave rise to a second process and the firm acted for another group of clients in that process. This resulted in further significant payouts for the firm’s clients and many millions to third parties.

The action was on behalf of a large group of women who suffered cancer misdiagnoses through negligence at Goodhealth Wanganui. (Some women were never treated for cancer conditions they suffered, and others suffered operations or other treatments when they did not have cancer at all). A leading edge case at the time on the availability of exemplary damages outside the statutory bar on personal injury actions (arising under NZ's statutory accident compensation regime). Litigation traversed many years but the case was ultimately resolved with the Crown offering a very attractive and beneficial statements to all clients.

An intellectual property case about patents valued at US$32M. The action was brought on behalf of the inventor of a novel reusable label system and was directed against a former business partner who had commenced a pirate manufacturing operation in Holland. GCA was able to force the Dutch company out of existence and the overall dispute was resolved completely in GCA's client's favour.

A derivative of the Lake Alice class action which alleged corrupt practices by government agencies in the course of the Crown making payouts to claimants following a second round of determinations by retired Court of Appeal Judge, Sir Rodney Gallen. Mr Zentveld's claims were upheld by the court and he received his full entitlement under the Determination, damages and costs. A very large number of other claimants were then correctly paid.

Following Liam's murder in the back of a Corrections Department's prison van GCA brought a successful action against the Crown.