A lawyer doubts new alcohol laws will make much difference to underage drinking, but the Drug Foundation hopes it will at least prompt conversations about teenage alcohol use.
The Sale and Supply of Alcohol Act comes into effect on Wednesday, and will require people giving alcohol to under 18-year-olds to have express consent from their parents or guardians.
A lawyer who specialises in liquor laws, Alan Dormer, says the Act will have minimal effect.
"It will have a significant impact on a few people, who will take this more seriously. But, so far as as the general population is concerned, I don't think it's going to have any impact at all to speak of."
Mr Dormer says the police rarely prosecute sale of liquor offences now and that's unlikely to change.
The executive director of the Drug Foundation, Ross Bell, hopes the law will prompt parents to talk to other parents about their teenagers' drinking.
He says it will also give people a chance to think about whether under 18-year-olds should have alcohol and ask what kind of environment should be created if they do.
The law allows for a fine of up to $2000 if a person provides alcohol without express parental consent.
