Police are "seriously considering" a permanent crackdown on speeding drivers by slashing the 10kmh tolerance they now allow.
The 10kmh tolerance allowed on the top speed limit of 100kmh has been cut to 4kmh over public holidays since 2010. The 4kmh tolerance is now being introduced for the rest of this month.
But Acting Superintendent Rob Morgan, national manager road policing, told The Dominion Post yesterday that a more permanent option was on the cards. "I would expect that in the long term we will be discussing whether we bring it in permanently or not.
"We are of the opinion that it's having a positive effect on the road toll. On that basis, we would be considering it very seriously.
"It will really be an evidence-based decision, it's about an assessment of whether it saves lives."
The 4kmh speed tolerance was introduced at Queen's Birthday Weekend in 2010 and has been used for all holiday weekends since. Police yesterday launched a Safer February campaign, reintroducing the 4kmh limit across all speed limits for the rest of the month.
Transport Ministry figures for 2009 show speeding was a contributing factor in 100 fatal crashes, 361 serious injury crashes and 1274 minor injury crashes.
A police spokeswoman said crashes during holiday periods since the change was introduced had fallen 46 per cent.
Mr Morgan said that, internationally, a reduction of 1kmh equated to a 4 per cent reduction in deaths. "At the end of February, we will consider the outcomes and, if the analysis supports it, we will consider further long periods or even permanently lowering the tolerance."
But motoring lobbyists doubt if a reduction in speed will achieve significant results.
Automobile Association motoring affairs general manager Mike Noon said: "We're not convinced that 104kmh poses any significant risk on our best roads. The focus should be on drivers who are going excessively fast, or extremely slowly."
Dog & Lemon Guide editor Clive Matthew-Wilson said the move would unfairly target innocent motorists, while failing to cut the road toll. "It won't make the slightest difference."
A high toll over the latest Christmas period showed the lower speeding tolerance did not work, he said. "Heavy policing does not lower the road toll."
The 10 per cent tolerance also allowed for variations in the accuracy of cars' speedometers, he said.
A reduced tolerance also relies more heavily on the accuracy of speed cameras, although Mr Morgan insisted testing equipment was reliable.
"Police could quite fairly say that we are going to apply no tolerance," he said. "We want to be fair to the public and tell them the tolerance we are applying."
But Mr Matthew-Wilson said many road deaths were caused by people who did not care about speed limits.
The recent reduction in the annual road toll was because of a combination of safer cars, safer roads and improved medical care.
Mr Noon warned that the public might not back a permanent lowering of the speeding tolerance. Getting the public on board was essential for road safety campaigns.
Transport Minister Gerry Brownlee said speed tolerance policy was an operational decision for the police commissioner. However, he expected the issue would be raised with him, if a long-term policy change was being considered.
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