"It is important that party organisers understand what the rules are.
"The safest way to put it is if you are hosting a party you have to consider yourself as the duty manager of your home."
While alcohol can be supplied to young people under the purchase age there are conditions.
The Sale and Supply of Alcohol Act 2012 allows for parents or guardians to supply alcohol to their own child or where express consent exists, then they may allow another person to supply alcohol to their child in a responsible manner.
"We want people to have a good time if celebrating their school ball, but we also want to ensure any such event is safe."
Police believe organisers and security staff should be proactive in managing the alcohol being brought into any gathering or event, take responsibility for those turning up intoxicated and do more to minimise the risk of alcohol harm.
"Police are wanting to prevent harm to young people and stop them getting into an unsafe situation due to alcohol."
For parents and caregivers looking for further advice on alcohol visit www.alcohol.org.nz
Police guidelines for throwing a before or after ball party
• Make sure you have spoken to the parents of all the young people you are supplying alcohol to and they have given their permission
• Have plenty of food and non-alcoholic drinks available
• Make sure everyone can get home safety
• Actively supervise your party to ensure young people have a safe and positive experience
• Limit the quantity of alcohol brought to an event by attendees