Police will face at least one big claim for compensation after police watchdog the IPCA found officers have been illegally shutting down parties.
The Independent Police Conduct Authority has investigated police actions at eight parties and has found that five were shut down illegally.
In 2009, Jakob Christie's neck was broken at a party in Wellington as police tried to clear it. Last year, Ella Eketone, who was 15 at the time, lost two teeth at an Auckland party when she was pushed by an officer trying to remove people.
Lawyers for both look set to make claims for compensation after the IPCA ruled that police mistakenly thought they could shut down parties without consent.
The IPCA said officers could end a party only with the consent of the owner or occupier or if there was a serious threat to people, property or emergency services.
Mr Christie's lawyer, Keith Jefferies, told Radio New Zealand's Checkpoint programme they will be seeking compensation - probably in excess of $40,000 or $50,000 because the injury has ruined his life.
"He was in a neck brace for some months. He was an apprentice plumber doing quite well at his job. Following that assault, he was unable to work, had to abandon his apprenticeship ... and can't really do any physical work."
Mr Jefferies says the claim will be made in the next few days and believed that police are still "in denial".
"When the report came out, they still denied that they hit the guy on the back of the head with a baton. The report found that he was hit on the back of the head with a police baton - there are only three ways that could happen - is the guy did it himself, the baton's out of the sky or the police did it. But the police don't acknowledge that."
Ms Eketone's lawyer, John Munro, said the family is considering its options.
Police say they now have a new policy to deal with out-of-control parties. Acting Assistant Commissioner of operations Sam Hoyle told Checkpoint they are open to discussing compensation with victims.
"We're open to talking to the individuals and their supporters," he said.
Police force at party 'excessive'
Police used unjustified and excessive force when breaking up the Auckland party during which Elle Eketone's teeth were knocked out, the IPCA found.
Ms Eketone lost two front teeth and suffered facial injuries after being knocked to the ground by an officer at a party in Howick in February 2013. At the time, 35 officers were trying to clear the party of about 150 people.
The IPCA's report on the case was released this morning and said police did not have grounds to suspect that removing partygoers from the property would prevent an emergency. It also said that Ms Eketone did not pose a risk to the officers.
The report recommends that police improve their training and monitor social media for upcoming parties.
Police accept recommendations
Police have said the officers acted appropriately, but in a statement earlier today said they accepted the IPCA's recommendations regarding the handling of out-of-control parties.
Police said they had already made changes, including giving staff clearer guidelines on how far their powers extended to parties on private property.
However, they noted the aspect of the report which said party organisers, attendees, parents and peers had a responsibility to ensure behaviour was safe and "appropriate."
They also said when police were called to parties the situation was often complex, rapidly changing and involved dealing with a large number of intoxicated people and fights.