If Nikolas Delegat was poor and Polynesian he'd be doing serious jail time, says the head of the Police Association.

Delegat, 19, beat a police officer so badly in March last year she was hospitalised and spent two months off work.

He kept punching her after she had been knocked out, and resisted arrest. He applied for name suppression and a discharge without conviction, but was denied.

On Monday he was sentenced to 300 hours' community service and ordered to pay $5000 in emotional harm reparation.

The Otago University student is the son of Jim Delegat, who heads the family-owned winemaking empire Delegat Group. Their wealth was estimated at $350 million in last year's NBR Rich List.

Greg O'Connor, president of the Police Association, says "big city lawyers" bullied Judge Kevin Phillips into not sending Delegat to jail.

"There's absolutely no doubt that had this lad not been able to afford the big lawyer that he did, he would be looking at some serious time," Mr O'Connor told Paul Henry on Tuesday.

"Had we been talking about a young Polynesian man from south Dunedin, then I'm sure we would have been talking whether it was 12 months or six months, or maybe even longer."

The judge was right not to discharge Delegat without a conviction or give him name suppression, says Mr O'Connor.

"I think the court of public opinion is where this judge and this offender are getting their justice."

But that might not last long. Mr O'Connor says the Delegat family are wealthy enough to hire social media teams and search engine experts to bury internet news stories about his crimes.

"The injustice just doesn't stop here - there's a lot of ways money can buy justice."

Mr O'Connor says the officer Delegat attacked, Alana Kane, is "not very happy" about the light sentence.

A Paul Henry poll showed 91 percent of viewers agree the sentence was too light.

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