A campaigner for medicinal cannabis wants a medical necessity defence introduced and a change in attitudes by doctors and the police.
The government will today unveil a law change to allow easier access to medicinal cannabis.
Medical Cannabis Awareness NZ coordinator Shane Le Brun said a medical necessity defence should be added to the Crimes Act or guidelines changed, to avoid prosecutions.
"The police really come down hard on cultivation, even for medical purposes ... we don't have to change the law and tell the police to stop prosecuting - but it could be a viable defence in court.
Prosecution guidelines for police could also be changed so medical necessity was a reason not to prosecute.
Since September, doctors have been able to prescribe cannabidiol (CBD) products without needing approval from the Health Minister. But ministerial approval is required before most cannabis-based products can be prescribed.
Mr Le Brun said the Ministry of Health's position was light years ahead of some doctors.
"If [the legislation] tinkers around, we're still going to have chronic pain patients having to go through an anaesthetist. All the anaesthetists in the public health system are pretty resistant to prescribing it and patients are going to have to go doctor shopping - which is less than ideal."
Mr Le Brun said growing medicinal cannabis products in New Zealand would be an important move, as the cheapest options from Canada were doubled in cost by shipping charges.
Health Minister David Clark said yesterday the legislation was as far as the government could go on medicinal cannabis and still have the numbers to get it through Parliament.
"We wanted to make sure that medicinal cannabis is more accessible to people with terminal illnesses or chronic conditions and the piece of legislation we will introduce will make progress."
'It's just a grow-your-own-dope bill'
Family First national director Bob McCoskrie said broadening access to cannabis for medicinal use was a smoke-screen for the long-term aim of legalising recreational marijuana.
Mr McCoskrie said in every other jurisdiction medicinal marijuana had led to decriminalisation and then to legalisation of cannabis use.
He said the Greens' bill allowing people to grow cannabis for medicinal purposes was "just a grow-your-own-dope bill".
It would be a mistake if legislation opened the door to people being allowed to smoke cannabis, he said.
"No other realm of medicine considers smoking therapeutic.
"We don't smoke opium to get the benefits of morphine.
"The New Zealand Medical Association just last month said it is difficult to justify a place for smoked cannabis as a medicine."
Medicinal cannabis in other forms needed controls on its quality, composition and how it was prescribed.
"Why not take a cautious approach?"
He expected the government legislation to be a more moderate version as New Zealand First had to agree on it.