Massey University's decision to cancel a Don Brash engagement has ignited debate about freedom of speech.

The man who lit the fuse leading to Don Brash's ban from speaking at Massey University's Manawatū campus has no regrets, and denies ever threatening anyone.

Karl Pearce said the students who organised it were naive if they thought there was no potential for conflict at the event, but he never intended to do anything more than wave a sign and make a statement in protest.

Pearce's letter to vice-chancellor Jan Thomas prompted her to pull the plug on the event, a call widely condemned as an attack on free speech.

Pearce said he supported her decision, but he thought commentators had misinterpreted what he wrote if they thought it was some sort of security threat.

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"Remember in light of their type of 'Free Speech' does not come Free of Consequences," he wrote.

Pearce said the consequences he was talking about were the hurt and possible backlash against those vilified by Brash's type of "separatist and supremacist rhetoric".

Students have responded to the university's action by organising a protest to be held at the concourse from 11am on Wednesday.

It is promoted as "protesting censorship of free speech", arguing students have the right to make up their own minds about issues.

JAY BOREHAM/STUFF Don Brash has been banned from speaking at Massey University.

Prime Minister Jacinda Ardern has called Massey's refusal to host Brash an "over-reaction".

Ardern said over the years there had been numerous examples of politicians and ex-politicians speaking on university campuses, often causing "a stir".

"This seems to me to be an over-reaction."

JANINE RANKIN/STUFF Karl Pearce's letter to Massey University vice-chancellor Jan Thomas resulted in Don Brash's speaking engagement being cancelled.

The university considered putting on extra security, but decided the risk of harm to students, staff and the public was too high against a backdrop of Brash's "support" for controversial Canadian speakers Lauren Southern and Stefan Molyneux.

Thomas said she supported free speech on campus, but totally opposed hate speech.

Free Speech Coalition spokesman David Cumin said Thomas' capitulation in the face of veiled threats about consequences from protesters was "disgraceful".

"Publicly funded universities in New Zealand and across the Western world have a proud tradition of upholding freedom of speech.

"If we allow the 'heckler's veto' to shut down contentious speech at a university, a place that should be a bastion of free expression, what hope can we have for free speech anywhere else?"

ACT leader David Seymour climbed into the debate, calling for Thomas' resignation.

MURRAY WILSON/STUFF Massey University vice-chancellor Jan Thomas has cancelled an event that was to feature former National Party leader Don Brash.

He said the former Reserve Bank governor and Opposition leader should be able to speak and express views some might disagree with.

Seymour said Education Minister Chris Hipkins should stop funding universities that won't protect free speech.

Hipkins said although the vice-chancellor's decision was not one he would have made, the university had the autonomy to make it.

He said universities should have a very high threshold around allowing free speech and robust debate.

Hipkins said to threaten the university's funding would, itself, be an infringement of its autonomy.

Thomas said the university's decision was not just about security.

"Mr Brash's leadership of Hobson's Pledge and views he and its supporters espoused in relation to Māori wards on councils was clearly of concern to many staff, particularly Māori staff.

"In my opinion, the views expressed by members of Hobson's Pledge come dangerously close to hate speech. They are certainly not conducive with the university's strategy of recognising the values of a Tiriti o Waitangi-led organisation.

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Brash has laid into the university for failing to uphold free speech.

"I believe the vice-chancellor's position is a disgraceful contradiction of publicly funded universities' role in hosting robust debate and the free exchange of ideas."

He pointed out the university cancelled the booking not just because of security concerns, but because of his involvement with Hobson's Pledge, his views on Māori wards on councils and "hate speech" concerns.

Brash said he supported the right of Southern and Molyneux, whose speaking engagement in Auckland was canned amid security concerns, to express their views. This was not the same as endorsing their views.

"It is clear that the thugs have been emboldened by Auckland Council's capitulation to protesters of the Southern/Molyneux event. This is why we are continuing our fight to defend free speech."

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Brash said he was also scheduled to take part in a debate at the University of Auckland on Thursday.

"We now fear that the University of Auckland too will give in to the vocal minority. The university must commit to providing a secure environment for free speech, lest it spark a domino effect that will wipe away the longstanding tradition of free expression on university campuses."

The University of Auckland Debating Society confirmed the debate would go ahead as planned.

"We think it is shaping up to be an incredibly interesting event," said its president, Chris Ryan.

WARWICK SMITH/STUFF Massey University has refused to host a meeting featuring Don Brash.

POLITICS SOCIETY 'DISAPPOINTED'

Massey University Politics Society spokesman Michael Curtis said the members were disappointed and a little surprised.

They invited Brash to talk about his time in politics, but were aware questions about his role in Hobson's Pledge could arise.

Curtis said they were not unduly concerned about security, but thought it prudent to raise an alert that a few individuals were making threats about causing problems.

"We felt it should have been able to go ahead, but we respect that is the vice-chancellor's executive decision to make."

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