The High Court has partially upheld a claim from a group of kiwifruit growers for damages over a PSA outbreak in 2010.
Watch a news conference with groups involved in the claim in Te Puke:
The Kiwifruit Claim group, representing 212 growers, sued the Ministry for Primary Industries (MPI) for negligence in allowing PSA to enter the country.
When the case went to court, the group wanted nearly $400m from the ministry to cover losses.
PSA, a vine-killing disease, is estimated to have cost the industry close to $900m.
Justice Mallon heard the case in the High Court in Wellington in August last year.
Lawyers on behalf of the growers argued the disease came in a shipment of pollen products from the Chinese province of Shaanxi, which the then Ministry of Agriculture and Forestry approved.
The Ministry for Primary Industries said earlier any liability on the Crown for losses as a result of a biosecurity incursion was covered by a statutory compensation scheme.
In her judgement, Justice Mallon said the ministry owed a duty of care to kiwifruit growers.
It had responsibility for controlling what goods could be imported into New Zealand and the risks of contamination should have been obvious.
Justice Mallon also found ministry personnel had not exercised reasonable care in preparing a research paper concerning pests and diseases associated with pollen.
She said the principal author and the supervisor of that paper had a different understanding of the scope of the paper.
That meant relevant information was omitted.
However, the ministry did not owe a duty of care to another plaintiff, the Kiwifruit giant, Seeka.
Justice Mallon said post-harvest operators were one step removed from the direct harm suffered by growers, so were less closely connected to the consequences of ministry negligence.
Kiwifruit Claim committee members held a news conference in Te Puke in response to the decision.
Committee member Grant Eynon said it was hugely significant that the court established that MPI owed a duty of care to kiwifruit growers in carrying out its biosecurity functions.
"Today is very significant day for the New Zealand kiwifruit industry.
"This is a landmark decision and we hope it draws a line in the sand for what has been a very long and difficult eight years for growers.
"The impact of this outbreak has been far reaching, not only on growers and their individual orchards, but on the New Zealand economy," Mr Eynon said.
Kiwifruit grower and committee member Bob Burt said the personal impact had been devastating.
"Some kiwifruit growers lost everything when PSA hit; their orchards, their business, their life savings.
"And for many the financial and emotional impact of the incursion is still ongoing."
Mr Eynon said biosecurity is critical to New Zealand, and primary producers and the economy are heavily reliant on MPI to protect New Zealand's borders against known biosecurity risks such as PSA.
"MPI knew for many years that PSA was a significant risk to the kiwifruit industry and we hope the government accepts the court's decision and the kiwifruit claim growers can be properly compensated," Mr Eynon said.
Committee member Stuart McKinstry said this was a two-stage case.
The first stage was proving the breach of the duty of care and the second stage will involve determining the level of compensation.
The group claims the losses incurred as a direct result of PSA were about $450m.
The committee said it was thrilled with the decision.
"It's good for all New Zealand, it's good for all primary industry," Mr Burt said.