Prime Minister John Key supports police plans for greater access to firearms, even though it would lead to more people being shot and he is unsure it would make police or the public safer.

Police Commissioner Howard Broad is working on a report into police access to firearms, including the possibility of having guns in lock-boxes in every frontline police vehicle.

The proposal has been described by the Police Association as a "minimum step" to counter violence against police officers; nine police officers have been shot in the past two years, two fatally.

Mr Key's tentative support for greater access to guns has not impressed association president Greg O'Connor, who believes it is inevitable that all frontline police will have holstered firearms, even though that has been ruled out at this stage by Police Minister Judith Collins.

Mr Key said yesterday that he would support the recommendations of the Police Commissioner, even though he had reservations about more guns for police.

"By definition you would think greater access to firearms would lead to more people being shot. One assumes that the very reason why you would give our police officers more access to weapons is because they would use them."

When asked if it would increase public and police safety, Mr Key said: "I'm unsure about that.

"If I thought arming the police was going to be the panacea to these problems, I would support it. But in countries where there is much larger propensity to arm police forces, there's no evidence that they're a lot safer."

Mr O'Connor had only two questions for the Prime Minister: "How many police officers will it take to be shot for him to change his mind? Is nine in two years not enough?"

He hoped to speak with Mr Key about the issue shortly.

However Mr Key said he would back Commissioner Broad if he wanted greater access to firearms.

"The moves the commissioner [is] making are understandable to arming more of the police and he'll have my support in that.

"If it comes down to protecting our police officers and the bad guys committing these crimes, I'm 100 per cent with the police. But in the real world, police officers actually have to make a call and I just worry that they may be apprehensive and in the end endangering their lives more than saving their lives."

Mr Key said he preferred the Taser because it was a non-lethal option, even though it had failed twice in recent weeks in hitting the target.

Last week in Christchurch, in an incident that resulted in two police officers being shot, a Taser was fired but it is understood the two Taser prongs did not hit the target.

On Sunday a Taser was fired in West Auckland but was ineffective. It is not clear why at this stage.

Mr Key said police officers had told him that if a person is high enough on drugs, the Taser can be ineffective.

But he still thought it was a good tool for police to have and it generally worked well.

"Every example I have seen of someone getting Tasered, most people hit the deck pretty quickly."