OPINION: The announcement by the police that a lower speed tolerance of 4kmh above the limit on the open road will be enforced over all of December and January will be supported by most people who use the roads.
A lower tolerance has been tried out over holiday periods several times in the last few years and each time fewer people have been killed and injured on the roads.
This will be the first time it has been tried over an extended period. It was a time last year when 57 people died on the roads and many times that number were badly injured.
The results this year will be watched with interest and Police Minister Anne Tolley has suggested that the lower tolerance may become permanent.
That may very well be a good idea but it needs to be examined in the wider context of speed limits generally. It is nearly 50 years since the open-road speed limit was set at more or less its present level.
Whether it is still appropriate for all roads in an age in which roads are designed and built to much higher standards and cars are immeasurably better engineered for safety may be questioned.
The toll of death and injury on New Zealand roads has fallen steeply since hitting its peak exactly 40 years ago.
Despite many more cars and other vehicles on the roads and many more kilometres being driven, the decline has been reasonably continuous and steady.
From the peak of 843 deaths in 1973 the toll fell to 284 in 2011, and although it ticked up slightly last year there is no reason to believe the decline will not continue.
Given that we still have a fatality rate 30 per cent higher than that of Australia, there is certainly still room for improvement.
Several factors have no doubt contributed to the decline. The compulsory wearing of seatbelts and better cars and roads are almost certainly among them, but uppermost is the disapproval that has grown over that time of drink-driving, along with heavy advertising and enforcement of the laws governing it.
The speed limit in that time has not changed. It is a truism - one heavily promoted by road-safety people - that the higher the speed the greater the mess when something goes wrong. That is true but beside the point.
All speed limits involve trade-offs between the need to keep traffic moving efficiently and the risk of accidents.
It would be possible to have a lower speed limit, and therefore less death and injury, but the cost in inconvenience in traffic movement means it would probably be flouted and only draconian enforcement could make drivers observe it.
More relevant is to have a speed limit that is appropriate for the road and conditions. For modern cars on some roads, the 100kmh limit looks too low.
The AA has suggested that a 110kmh limit on motorways and the like could be introduced without compromising safety.
That would bring New Zealand into line with the likes of Australia, Canada, France and Britain, all of whom have better road safety records than we do.
Surveys suggest that is the average speed on the open roads already.
Making it the new limit and making it clear it would be strictly enforced would therefore be no great change. By reducing driver frustration, it might even improve behaviour on the roads.
- © Fairfax NZ News