Retiring Chief Coroner Judge Neil MacLean says he fears that coroners will lose their powers in a review of the Coroners Act this year.
Judge MacLean gave the warning this morning at a press conference marking his retirement.
Judge MacLean was appointed the first chief coroner under the Coroners Act of 2006.
He said New Zealand was a forerunner in coroners' work but it had slipped behind other countries which have a mandatory response to coroners' recommendations.
The judge said coroners do not make recommendations lightly and there is nothing to stop a powerful organisation from ignoring them.
He said the review of the Coroners Act was sending the message that their powers needed to be trimmed.
"It's in areas like the ability of police to question a coroner's direction, as to whether or not it's reasonable; the shutting out of coroners from combat deaths in the defence force; making it a little vague as to our powers about a post-mortem."
Judge MacLean warned there would be more quad bike deaths unless reforms were made as recommended by coroners.
And, for the first time, he spoke out on the legal drinking age, which he said should be raised to 20.