However, the vision and images only provide a snapshot of the demonstration, which means the outcome of the case could be determined by the strength of police, plaintiff and other witness evidence.
Brown said he was motivated to become lead plaintiff, in part, by the need to protect basic civil and political rights.
“There’s ample footage of the protesters being indiscriminately sprayed and what this case is about is holding the police to account for those actions and decisions,” he told The Age.
The 37-year-old documentary maker said he attended the conference to voice his opposition to the mining industry and its impact on global warming and the environment.
A Victoria Police spokeswoman declined to comment while the case was before the courts. However, the Police Association launched a strident defence of its members.
“Everyone has the right to peacefully protest, but that does not provide an unfettered right to blockade, beset a premise or restrict the lawful activities of others in the community,” an association spokesman said.
“Our members are always caught in the middle of events like this, as they concentrate their efforts on maintaining the balance between the rights of protesters and the rights of others in the community.”
The spokesman said four officers were injured during the demonstration. The clash could have been avoided, he said, had protesters responded to officers’ lawful directions.
Brown was standing outside the convention centre just before midday on October 30 when two protesters climbed poles and unfurled a banner which read: “Blockade IMARC for Climate Justice.”
As they descended a short time later, officers from the Public Order Response Team tried to arrest the pair and ordered other protesters move out of their way.
According to the writ, several officers used capsicum spray for about one minute, even when Brown and other protesters retreated. Police are also accused in the writ of a “series of batteries and assaults” as they attempted to arrest the climbers and disperse about 100 protesters.
Brown will pursue aggravated and exemplary damages in the Supreme Court, after he allegedly sustained injuries including acute burning of the skin and eyes, itchiness, bruising and psychiatric harm.
Inner Melbourne Community Legal principal solicitor Gregor Husper hoped the case would place greater scrutiny on police powers.
“We’re concerned about the rising militarisation of Victoria Police and the protection of protest rights under Victoria’s human rights laws,” he said. “The rights for peaceful assembly and freedom to demonstrate are integral to a functioning democratic society.”
Olivia McMillan, a special counsel at law firm Phi Finney McDonald, said the class action was unique in the manner it focused specifically on the use of OC spray.
Police have previously faced legal action for using capsicum spray during protests.
In July, the force paid a settlement worth thousands of dollars to an Age photographer who was pepper-sprayed twice in the face by officers while covering an anti-lockdown protest.
Luis Ascui was sprayed directly in the eyes while photographing a rally in Richmond in September last year, even though he had identified himself as a media representative. He was carrying three cameras and wore media accreditation. Police did not admit wrongdoing when settling the case.
In 2007, the force settled a case with 47 protesters who alleged officers had used improper force during the World Economic Forum protests in 2000. Despite the settlement, reported to be $700,000, police insisted its response was appropriate.
Lawyer Jeremy King, who is not involved in Brown’s case but has launched unrelated and successful civil actions against police, said the class action would be vigorously contested.
“Without commenting on this specific case, it has always been my experience that Victoria Police fight hard in civil litigation and these matters are often long and drawn out. You need robust and brave individuals to go down the path of litigation against police,” King said.
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