The rules governing the serving of alcohol to under-18s at after-ball parties need to be clarified, Law Commission president Sir Geoffrey Palmer says.
A month after the commission called for the biggest shake-up to the country's drinking laws in 20 years, Sir Geoffrey said he saw many problems with after-balls,and the legal consequences of holding such events were "a vexed issue".
Sections of the Sale of Liquor Act relating to the purchase of alcohol for minors needed to be adjusted to avoid confusion, he said.
One section says anyone who buys liquor intending to supply it to minors is liable to a fine of up to $2000.
But another section says that law does not apply to anyone who is a legal guardian, or anyone attending a private social gathering.
These definitions became dubious when parents had signed consent forms, minors had bought tickets and the parents were not the ones giving out alcohol, Sir Geoffrey said.
"This law needs attention."
Alcohol Advisory Council chief executive Gerard Vaughan said organised after-balls did appear to be in breach of the Sale of Liquor Act.
"An event such as this where from news reports people were paying for tickets and alcohol was to be supplied would almost certainly not be regarded as a private social gathering and would be subject to the restrictions in the act.
"Therefore only a parent or guardian who was present at the event could we believe legally give alcohol to a minor."
In advice sent to Auckland City Council, Auckland City Police liquor licensing co-ordinator Jason Loye said he thought people hosting after-balls would not fall under the requirements of a "private social gathering".
The event organisers would be liable for a $20,000 fine if alcohol was consumed without a special liquor licence, and alcohol would have to be restricted to people 18 or over.
Sergeant Loye said police would be happy to discuss the organisation of events to ensure they were correctly run.
