The Government is considering how to better support officers following a series of "barbaric" assaults.

After three separate assaults on police in three days, Prime Minister John Key has floated the idea of creating a special category of offence for assault on a police officer, or requiring judges to give weight to an officer's occupation when sentencing their attacker.

The Police Association welcomes harsher penalties, but says it will not solve the problem alone, while one expert warns that stiffer sentences will generally not discourage such attacks.

"People, when they commit these kind of offences, are acting in a frenzy," said criminologist Greg Newbold.

"They are not acting rationally. They don't think about the consequences of what they are doing."

The Government is awaiting a report with recommendations from the police in the coming days, but Mr Key said a special case for police over ordinary citizens in assault cases was warranted because they were called out to dangerous situations.

"I think New Zealanders will reflect that their last line of defence is the police force. When we see the things we saw last weekend, I think most New Zealanders were offended by that. They were barbaric acts and quite frankly disgusting.

"If anyone thinks the Government is going to sit back while police officers' lips are being bitten off and do nothing about it, then they need to think again."

Association president Greg O'Connor said tougher sentences needed to be focused on the "lower end" of offending against police.

"Generally people get reasonable sentences for attacks on police anyway, particularly serious attacks. It's the lower end attacks that actually have to be treated more seriously. Police should not have to put up with being [verbally] abused."

Police Commissioner Howard Broad agreed, saying:

"It is the way of the world that if you are not confronted about the small things that you do that offend, then you are emboldened to do other things you think you can get away with."

Professor Newbold said some young criminals would assault police just to get "street cred".

In the latest attack, in Oamaru on Sunday night, a police officer was assaulted by a group of people when carrying out a drink driving test.

The officer was brought to the ground and kicked repeatedly. He was treated for injuries to his face, elbow and knee. Three men appeared in court yesterday in relation to the attack.

A Whangarei police officer was discharged from hospital yesterday after surgeons reattached his lower lip, bitten off during an alleged assault by a suspected drunk driver in Kamo on Saturday night.

Reo Rangipohewa Uerata, 29, appeared in Whangarei District Court on six charges relating to the incident, including assault, resisting arrest and disfigurement by grievous bodily harm.

Police Minister Judith Collins said a clear message needed to be sent that an attack on police was an attack on "our entire system of law."

Figures released by Mr Key yesterday showed that attacks on police officers over the past decade rose from 216 in 1999/2000 to 412 in 2008/09.

Mr Broad said while there had been a marked increase in serious assaults in recent years, it was still a low number.

Dr Newbold said the risk of being assaulted could be seen as "part and parcel" of being a police officer.

"Police are trained how to try and defuse situations like that, with body language and talk, and to retreat if they are in danger.

"But there are some situations that just get completely out of control, and you are just stuck there, and you are going to get a hiding. It must be a nightmare for them."