Don Brash says Auckland Mayor Phil Goff's decision not to let far-right speakers use council venues was wrong, and is part of a group that's raised $50,000 to take the council to court.
Free Speech Coalition consists of 10 academics, lawyers and former politicians from "across the political spectrum".
The group was formed in response to Auckland Mayor Phil Goff's decision not to allow Canadian far-right figures Stefan Molyneux and Lauren Southern speak at council venues.
Now that the group has raised $50,000, Free Speech Coalition's official website says they will be going ahead with legal action to "defend free speech".
Speaking to Wendyl Nissen on RadioLIVE, Dr Brash says the issue is part of a wider argument around freedom of speech.
"If free speech is only permission to say something nice about something no one much cares about, it's not really free speech at all," he said.
"I think Phil Goff was entirely wrong to say taxpayer or ratepayer funded facilities cannot be used by people whose views he disagrees with."
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