A victim of two off-duty policemen yesterday found guilty of a drunken assault is calling for justice after their bid for a discharge without conviction.

Auckland District Court Judge Heather Simpson yesterday rejected claims that former Auckland City constables Patrick Garty, 32, and Wiremu Bowers Rakatau, 21, acted in self-defence when they kicked and punched a group of students in March.

"[The students] held out their arms from the sides of their bodies, had hands open with fingers splayed, palms pointing forward, reasonably indicating a non-aggressive, even conciliatory way of behaving," Judge Simpson said in finding Garty guilty of three charges of common assault and Bowers Rakatau guilty of one - as well as another joint charge for the pair.

The court heard that the officers first spotted the group in High St, pushing a shopping trolley, and ordered them to stop because they feared shop windows, parked cars and buildings would be damaged.

The students obeyed immediately, but the policemen followed them up the street and into Little High St.

Police officer Chris Renata was with them, but is to be tried separately.

"You had plenty of opportunities to retreat from the field of battle and plenty of opportunities to choose other methods to deal with what you perceived as inappropriate behaviour," Judge Simpson said.

The officers' lawyers, John Anderson and Kevin McDonald, immediately indicated they would apply for discharge without conviction under Section 106 of the Sentencing Act.

This allows a judge to rule that the gravity of offending does not outweigh the need for conviction.

Speaking to the Herald last night, one of the men attacked, Thomas Campbell, said the policemen should be convicted to show the "justice systems works".

"No one should act like that in society - let alone police officers."

Bowers Rakatau had earlier told the court he repeatedly kicked one student because he was one of three advancing and he believed three more were lying in wait.

"I distinctly remember quite a big guy in a green hat and a few more people around him," he said. "Then him taking a step towards me ... It was enough for me to feel threatened."

Bowers Rakatau said he was protecting Garty, who was too drunk to defend himself.

But Judge Simpson said he was keeping the students back while Garty assaulted Benjamin Palmer.

Footage played in slow-motion showed Bowers Rakatau, with his back to the camera, advancing on the green-capped student and kicking him with his right leg. The man did not fight back as he retreated.

Judge Simpson said the pair should have "stood sentinel at the mouth of Little High St and called police".

Michael Bott, chairman of the NZ Council for Civil Liberties, stressed the applications for discharge without conviction were not a given.

"It's not a get-out-of-jail card and is by no means guaranteed because Section 107 of the Sentencing Act says it has to be [proven] disproportionate."

The court heard that Garty had left the police and was working at a steel factory in Queensland. But his lawyer did not rule out a career with Australian police.

Police spokeswoman Noreen Hegarty said Bowers Rakatau was "on a variation of duties while suspended from normal duties".