The Police Commissioner is considering putting more guns in patrol cars in response to a rising number of assaults on frontline staff.

Howard Broad says three attacks on officers at the weekend have prompted police to explore ways of deterring such assaults.

A policeman was beaten unconscious by teenagers outside Tuakau College, south of Auckland, on Friday, another had his lip bitten off by a suspected drink-driver in Whangarei, and a third was attacked by a carload of people in Oamaru on Sunday after the driver failed a breath test.

Mr Broad said yesterday that one option being considered to protect officers was to keep guns in car boots.

But the idea has appalled civil libertarians, who say putting guns in patrol cars would only encourage criminals to attack, and turn New Zealand into a Third World country.

Barry Wilson, president of the Auckland Council for Civil Liberties, said the commissioner needed to "just be honest" and admit that the real debate was about arming police.

"This is a cynical piece of opportunism in response to situations which are examples of extreme violence against police," he said. "They can't justify the issue of arms to police as a result of the public feeling outraged."

Mr Wilson said what Mr Broad actually wanted was for police to have "guns on their hips".

Mr Broad said he was opposed to such a move.

Police spokesman Jon Neilson said senior sergeants, section sergeants and specialist units carried arms in their cars at present.

But Mr Broad is looking at expanding access to guns across the board.

Mr Wilson said having guns in cars would not have helped any of the three officers attacked at the weekend.

Mr Broad said another option to protect officers was to toughen up penalties for "mid-range" attacks.

"Current penalties for offences at the most serious and minor ends of the scale seem appropriate - the worst perpetrators of grievous bodily harm face up to 14 years in prison.

"But we will look closely at offences in the mid-range, and also those involving a weapon or where people attack as a group. Anyone who picks up a weapon or joins in an attack has made a deliberate decision, and should face additional consequences."

Last night, Police Association chief Greg O'Connor said any talk of increasing firearm availability was good.

"This absolute squeamishness we've had in New Zealand, governed by irrational criticism when police officers have used firearms, has governed policy rather than practical needs and it's time that changed."

He said there had never been an unjustified shooting by a NZ police officer, "despite the critics".