Legislation laying out new rules for the sale of party pills and other so-called legal highs has passed its first reading in Parliament on Tuesday.
The Psychoactive Substances Bill requires party pill manufacturers to prove that their products are safe before they can be sold.
It would apply to any product containing psychoactive material, excluding alcohol and tobacco, or those covered by the Misuse of Drugs Act.
Parliament's health select committee will now consider the bill.
Associate Health Minister Peter Dunne says scores of products with unknown effects and risks have slipped through a regulatory void and onto dairy shelves.
Mr Dunne says the legislation to fix that is game-changing and will be in place by August this year.
But the Labour Party says it resents being asked to effectively rubberstamp legislation that would allow some drugs to be sold legally.
MP Iain Lees-Galloway says his party supports the bill, but a month for select committee hearings - as requested by the Government - is too short.
"This is actually quite a significant piece of legislation. It is the first time New Zealand has said we are going to have a mechanism in legislation by which drugs can be made legal - and it's not something we should be rushing."
Mr Lees-Galloway says hearings are important to discuss potential anomalies, for example why products such as kava are not covered by the bill.
