Anyone vaping or smoking with kids in the car could be hit with a $50 fine.
The Government is moving to ban lighting up in vehicles when anyone under 18 is inside.
It will apply to vehicles whether they're parked, or on the move.
Associate Health Minister Jenny Salesa expects the law to be changed by the end of this year.
She told the Weekend Collective that it will be up to the police to enforce the law.
"After a lead in time of 18 months, police will have the ability and the discretion to issue an infringement fee of $50. Alternatively, police can issue warnings or referrals to support services."
She says that there were several discussions amongst politicians, police and various Ministries in order to find the right fine. The $50 fine was seen as an acceptable level of enforcement.
"The reality is that those smoking are from those in lower socio-economic areas. We did not want the fine to be such a struggle for them."
Salesa says that she wants the fines to be kept to an absolute minimum. She wants the law to be used as a guidance that will alter people's opinions.
She says it's about educating families.
"We're looking more at people changing their behaviour rather than police issuing infringement notices."
Salesa says public education and social marketing campaigns over many years have had some impact.
"But the rate of reduction to children being exposed to smoking in vehicles has begun to slow. It is time for us to introduce legislation."
She says multiple other countries have similar legislation. She says in the United Kingdom, only one case went through the court system.
Salesa expects the law to be changed by the end of this year.
The Children's Commissioner wants politicians to work together to make a new law succeed.
Judge Andrew Becroft says children's health comes first.
"My plea to all politicians is let's make this cross-party. This can't be a political football and meshed with political mumbo-jumbo about freedom of choice. Children don't have choice."
Becroft says there's no reason why you can't smoke outside.
He hopes that the law doesn't stop with cars.
"I hope we do get to the point, maybe in decades to come, when it will be unlawful to smoke in the home."