Police Commissioner Mike Bush has admitted the summer road-safety campaign was confusing to motorists.

Police kicked off the campaign on November 28 by saying anyone exceeding the speed limit over summer could expect to be pulled over.

There would still be a 4kmh tolerance on fixed speed cameras, they said, but their message that officers would have a zero tolerance to speeding was met with a public backlash.

Bush today acknowledged there was some confusion over the police messages about the campaign and it had become an issue many New Zealanders were passionate about.

"The purpose of the campaign was to save lives on our roads," he said.

"However, some members of the public have told us that our messaging was not clear enough around what speed levels would be enforced. I acknowledge we should have been clearer.

"We should have been explicit that speed cameras were set for usual holiday tolerance of more than 4kmh over the limit and that roadside officers would continue to use their discretion in stopping people driving over the speed limit, but would focus on unsafe driving behaviours.

"Our staff have been using their discretion appropriately over the summer campaign."

By yesterday, 14 tickets had been issued to people travelling between 1kmh and 4kmh over the speed limit since December 1, he said.

In comparison, 13 tickets were issued in that speed band for the 2013-14 summer campaign, from December 2013 to January 2014.

Future road policing campaigns would have clearer messaging, Bush said.

"Local and international experience demonstrates that when we all slow down, deaths and serious injuries decrease and the roads are safer and calmer for all," he said.

"There will now be a review of the messaging in the Safer Summer campaign, and the lessons learnt will be incorporated into future campaigns."

The review, requested by Police Minister Michael Woodhouse, would begin after the campaign concluded at the end of this month.

Hours after appearing as a guest on a talkback radio show yesterday, Woodhouse said he had asked police to review all the public messages they put out as part of the 2014-15 summer road-safety campaign.

He said there was widespread confusion about the summer programme.

"A zero-tolerance message did go out but I think the fact was that zero tolerance was for very poor driving behaviour that would lead to death and injury on our roads," he said.

"Police maintained a discretion. The speed cameras had a 4kmh discretion, but I accept there may have been some confusion in the mind of the New Zealand public around what those discretions were."

The use of the term "zero tolerance" had led people to believe there would be no discretion on the speed limit, he said.

The Automobile Association said it was "inundated" over the holiday period with calls from drivers confused about the police stance.

"Our members were really confused by the campaign," AA general manager of motoring affairs Mike Noon said.

"The police announced there would be a zero tolerance but then more quietly said, 'No, we will enforce it within 4kmh'."

The only person who has so far defended the police is Labour leader Andrew Little.

He said yesterday that police needed time to investigate the circumstances of each accident before leaping to any conclusions.

Little backed the police, saying he saw no problem in "sending a signal when you know that there are peak travel times, saying that you are going to strictly enforce the law".

"[For Woodhouse] to go on to a talkback show and get roasted and decide you are going to do something then it looks, frankly, just a little bit flaky to me," Little said.

"If there is a debate about whether there should be a more varied range of speed limits - some open roads can accommodate 110kmh and some can't - that is a separate debate and we should have that at some point.

"But I am a little bit uncomfortable about this climbing into the police for enforcing the speed limits."