Failed Crafar farms bidder and fraud case defendant May Wang has failed to bar Hong Kong prosecutors from accessing seized documents.
Companies associated with Wang are appealing the decision through the Hong Kong courts.
The documents included correspondence from New Zealand lawyers who dealt with Wang or companies associated with her.
Wang, with co-accused Keen Chen and Wenjye Yee, face charges for conspiracy to defraud laid by Hong Kong's Independent Commission Against Corruption (ICAC).
The businesswoman, who also goes by the name May Hao, is best known in this country as a failed purchaser of 22 North Island dairy farms, known as the Crafar Farms. Sixteen of these farms were eventually bought in 2012 by China's Shanghai Pengxin for a sum thought to be about $200 million.
The events leading up to Wang's failed purchase of the farms form the crux of ICAC's case against her, which may go to trial later this year. Wang does not face any charges in New Zealand.
According to prosecutors, Wang and Chen allegedly induced Hong-Kong listed firm Natural Dairy to acquire the Crafar farms from one of her companies.
This company, according to prosecutors, did not own the farms but would purchase them with Natural Dairy's money in the name of another of Wang's firms, UBNZ Assets Holdings.
Natural Dairy would, in turn, own UBNZ Assets Holdings and therefore the dairy farms.
Although the Crafar farms were allegedly on the brink of bankruptcy, Wang and Yee are accused of falsifying their accounts so they appeared to be in substantial profit.
The trio are also accused of failing to declare that Chen and Wang had an agreement to share the commission arising from the sale and purchase of the farms.
Unaware of this relationship, and ignorant of the true state of the farm's finances, prosecutors say Natural Dairy approved the acquisition and in 2010 raised HK$955 million ($186 million) to finance it.
Funds to buy the farms were allegedly transferred into a trust account of Auckland law firm Knight Coldicutt, which also had done work for companies associated with Wang.
Four of the 22 farms were purchased for $25.5 million in February 2010 and in May a deposit was paid for the remainder of them, pending Overseas Investment Office (OIO) approval of the transaction.
But later that year Wang was declared bankrupt in New Zealand and then arrested with Chen in Hong Kong. A week later, the OIO refused to grant permission for the purchase of the remaining farms.
After being declared bankrupt, prosecutors allege Wang set up a firm called NZ Dairy Trustee which, following a series of transactions, held the four farms and the shares of other companies associated with her, such as New Zealand Dairy Processing.
It is alleged that the directors and shareholders of NZ Dairy Trustee were Wang's nominees.
In January 2011, NZ Dairy Trustee, allegedly received a cheque for $23 million, almost $10 million of which was transferred to a company called Super Worth International.
Super Worth's Hong Kong offices were searched by ICAC in 2012 and documents from it were seized. These documents included a fee notice issued by Sargent Lawyers and emails to Wang from Knight Coldicutt's Kerry Knight, who has since left that law firm.
Wang, Super Worth, NZ Dairy Trustee and New Zealand Dairy Processing claimed these documents were legally privileged, which would mean prosecutors would not be able to view them. A hearing to decide the claim took place in Hong Kong in June, with ICAC arguing a "fraud exception" meant legal privilege over the documents was lost.
Deputy High Court Judge John Saunders said in his decision last month that the claim for legal privilege "comprehensively failed".
"There is a clear and very strong prima facie case of fraud in relation to May Wang's alteration of the Crafar Farms accounts," the judge said.
"The activities that she undertook following her bankruptcy, using Super Worth, NZ Dairy Trustee and New Zealand Dairy Processing and other companies, were activities which, prima facie, appear to be designed solely to conceal her involvement with the farms that she had acquired as a result of the fraud, and to release the funds from the sale of those farms from companies used by her as vehicles in the purchase and sale," he said.
"I am accordingly satisfied that any legal advice given in respect of the activities involved in the incorporation of the various companies, the appointment or resignation of directors of those companies, the changing of shareholding in the companies, and the movement of funds are activities which by reason of the fraud exception cannot be protected by LPP [legal professional privilege]," Deputy Judge Saunders said.
The decision is being appealed.
•May Wang was the failed purchaser of 22 North Island dairy farms, known as the Crafar Farms.
•Sixteen of these farms were eventually bought in 2012 by China's Shanghai Pengxin for a sum thought to be about $200 million.