The Police Assocation wants promoters of big events to foot the bill for their policing.
The union says the policy should be applied to profit-making ventures such as sports events, concerts and wine and food festivals.
Association president Greg O'Connor says the current system is flawed and charging is common in other countries.
Mr O'Connor says the policy should not be applied to non-profit public gatherings, such as free concerts, fireworks and New Years Eve celebrations.
He says the police surveyed people on charging for services in 2007 and 73% were in favour of it.
Police say they are keeping the option under review.
