A Government ban on the sale of all synthetic cannabis products could spark legal action from the industry, a retailer says.
An urgent bill to ban synthetic cannabis such as Kronic will be considered by Parliament today.
Associate Health Minister Peter Dunne said the law would be in place by Friday and all 43 current products on the market were expected to be out of shops just over a week later.
Cabinet has approved amendments to the Misuse of Drugs Amendment Bill that would take synthetic cannabis off the market for 12 months, while the Government works on its detailed response to a Law Commission report, which recommends reversing the onus of proof and require the industry to prove its products are safe.
Hemp Store co-owner Chris Fowlie said the Misuse of Drugs Act required the classification of drugs to be based on evidence and Mr Dunne was ignoring that.
"Certainly some people might look at litigation to see whether the Government has to conduct the research that the law says it needs to do," he told TVNZ's Breakfast.
Mr Fowlie said the industry had been supportive of putting synthetic cannabinoids into Class D, which would restrict their sale to people over the age of 18, but Mr Dunne had since changed his mind.
"We've spent the last few weeks developing new packaging, arranging testing of products, we've invested thousands of dollars in the last few weeks to gear up for Class D. And now that he's banned it we might see some of that cooperation disappear."
A lack of legislation allowed the sale of the products to go too far.
"It took too long and things got out of control, but we don't need to lurch from a situation of no rules whatsoever to an absolute ban," he said.
Mr Fowlie said retailers would dump stock, with the Hemp Store planning to have a big sale to "get rid of everything we've got".
New products would come out immediately after the ban, but rather than the products all coming out at once, manufacturers would "drip-feed" them so there will be a certain period to sell them.
"You'll get six months to four years maybe of selling it, then you'll put up the next one."
Asked about the possibility of a legal challenge, Mr Dunne told TVNZ's Breakfast there was plenty of evidence to ban the products.
"There's a lot of evidence available through hospital emergency rooms, coming from the National Poisons Centre, even the expert advisory committee in its early report late last year identified risks for potential damages," he said.
"Some of it's anecdotal, some of it is scientific peer-reviewed data. There's ongoing work being done in all of these areas.
"The bottom line is right around the world these issues cause concern, these materials are causing concern and government's are seeking to act."
Mr Dunne said the new regime would be robust and disagreed it had taken too long.
"It was important to get it right and I make no apology for taking the time to get it right, and I think we have done that, and we will have a comprehensive ban," he said.
"It's not just synthetic cannabinoids that are affected here, it's any potential psychoactive substance that the minister feels has potential risks associated with it.
"So this is quite a wide-ranging measure, and there will be an element of having to respond to new products coming on the market, but the power to do so is quick and that will happen within a seven day period."
