Doctors say secret doses of medicinal cannabis oil given to a teenager by his mother could have harmed him.
Rose Renton has admitted giving son Alex cannabinoid oil (CBD oil) before official approval was granted.
Associate Health Minister Peter Dunne says it was unwise.
Ms Renton says she has no regrets about giving her son secret doses of CBD oil as he lay in a coma.
The family were fighting for approval to use the oil to treat his seizures. That was granted in mid-June, but Ms Renton admitted to 3D she started giving it to the 19-year-old three weeks before.
"Yeah I gave it to him," she says. "When no one was around I'd put it down the back of his mouth with a syringe."
Mr Renton passed away just three weeks after receiving his first legal dose.
3 News had arranged to talk to Ms Renton this afternoon, but she cancelled all interviews after telling RadioLIVE her admission of the early dose was obscuring the real issue – freedom of choice.
"Obviously as a mum I will be on Alex's case for the rest of my life, but the real issue here really is the issue of freedom of choice."
Mr Dunne, who approved the one-off use of the oil on compassionate grounds, says the early dose was unwise and unfortunate, and doesn't set a precedent.
"There is no precedent," says Mr Dunne. "Any future case will be treated strictly on its merits."
He says Mr Renton's case shouldn't be used as an argument for legalising cannabis.
"What makes me angry is a number of other people associated with her who made it so blatantly obvious for legalising cannabis full-stop, and that is not going to happen."
Capital and Coast DHB says such an early dose could have caused harm and unauthorised use could lead to legal proceedings, but it's not the DHB's role to initiate charges.
Police say they're seeking further information on the case.