Police and the City of Armadale aim to prosecute two hosts over WA's worst out-of-control party, with the teenagers potentially each facing fines up to $15,000.
George Peppas and Brady Robinson are among 12 people aged 15 to 22 charged with 21 criminal offences over last Saturday night's wild gathering where police were pelted with glass bottles, bricks and other debris when they tried to disperse about 500 people from a disused shed in the southern suburbs.
Acting Insp. Chris Adams said the organisers had each been charged with trespass and issued with $1000 liquor infringements for allowing juveniles to drink.
He said police and Armadale council were looking at prosecuting the pair over several alleged offences under local government bylaws that come with fines of up to $15,000.
Police also lodged a tax evasion report with the Australian Taxation Office over profits the organisers allegedly made by charging an entry fee.
The teenagers advertised the party on Facebook but claim they tried to cancel the event at the last minute and left the scene before police arrived after realising it was spiralling out of control.
Acting Insp. Adams said the incident showed technology such as mobile phones and social media helped spread word of a party but could have dire consequences because it took away the ability to control a situation.
Police went to the party after complaints from nearby Piara Waters residents and by 9pm the riot squad had arrived.
More than 70 police officers with horses, dogs and a helicopter spent more than four hours trying to move on the mainly drunk teenagers.
Police believe the number of projectiles thrown and the size of the crowd made it the worst party they had attended.
Armadale council used a front-end loader to clean up glass, rocks and pavers. Police launched Operation Esryn to target troublemakers and the violence put pressure on the State Government to bring in a Bill to tackle problem parties as its top priority.
Police Minister Liza Harvey said she hoped to introduce the legislation into Parliament next week but with just 16 sitting days left, its passing into law is not guaranteed.
Acting Commissioner Chris Dawson said the arrests should send a warning to revellers that police would pursue anyone who committed a crime at unlawful assemblies.
Two people who allegedly threw bottles and rocks at police have also been charged and could be jailed.