Felicity Perry, Arthur Price and Simon Oosterman were acquitted of all charges relating to the protest against genetically engineered trees in Rotorua.

They had pleaded not guilty to charges of obstruction and resisting arrest.

In his judgement, Judge Weir stated that police had failed to exercise "tact, tolerance and restraint, and use of powers reasonably and properly, [which] appear to have been more observed in their breach than their compliance. The use of OC spray raises more questions than it answers".

"Global Peace and Justice Auckland supporters have had wide experience of police action in protests over several decades," said John Minto, teacher, seasoned activist and GPJA spokesperson.

"We have experienced first hand police tactics which have too often led to violence and disorder while policing peaceful protest. We are also well aware of the long-standing, deep-seated, simmering resentment of protest groups by the police.

"However the use of pepper spray in peaceful protest is a dangerous escalation in thuggish behaviour," he said.

Union organiser and climate justice campaigner Mr Oosterman said: "Being pepper sprayed at a peaceful protest is the latest in a series of personal experiences of police overreaction and brutality.

"The judge dropped all charges against us," said Mr Oosterman, "and at the time of the original hearing said the police had incriminated themselves more than the defendants and he was going to send his ruling to the police commissioner.

"While politicians are busy fighting over the reputation of the police, the police continue to use brutal tactics and restrict peoples' civil liberties.

"My own personal experience over the past year, where I have been grabbed by the throat in an illegal manner, arrested for whistling at another demonstration and then pepper sprayed at Rotorua, smacks of police brutality, negligence and lack of police judgement," he said.