Let the people decide how much

That raises an interesting question. When the law says one thing and a large majority of people demonstrate they have a different view, which prevails? If the law is supposed to reflect the values of society, as is supposedly the basis of the common law and a key expectation of democracy, the law is clearly wrong. Only in a dictatorship do we expect the ruler to insist the people are wrong.

The way some public servants and politicians talk, you could be forgiven for thinking that the policy objective of traffic laws is to reduce accidents and deaths to zero. Yet that is clearly nonsense – accidents causing death and injury are inevitable at any speed above walking pace. The road toll could be immediately stopped by reducing speed limits to 10 km/hr or by banning cars.

Clearly, there is a trade-off. Explicitly or not, we accept a certain level of accidents as the price of convenient travel, as we do in numerous other activities. What is apparent from the fact that so many drivers disobey the speed limits when they have the opportunity is that the trade-off needs recalibrating. And rather than public servants deciding what it ought to be, the community as a whole should do it.

There is an internationally recognised method by which this can be achieved, known as the 85^th percentile formula. In essence, it involves the temporary removal of the speed limit while speeds are monitored. At the conclusion of the period, a limit is reimposed at or slightly above the speed at which 85 percent of drivers travel.

The concept is based on the assumption that the large majority of drivers are reasonable and prudent, do not want to have a crash, and wish to reach their destination in the shortest possible time.

It is supported by statistical evidence, which shows that those who exceed speed limits based on the 85^th percentile are substantially more likely to cause accidents (as are those who travel below the 15^th percentile). Enforcement directed at these drivers thus has a positive impact on road safety while enjoying community support and avoiding perceptions of revenue-raising.

If the formula was applied to Australian roads, speed limits would certainly be increased on our major highways, probably to European levels. There may also be increases on some dual carriageways in metropolitan areas, although it is unlikely most suburban streets would change. Given that most drivers are indeed reasonable and prudent, there might even be a few reductions.

Notwithstanding the flawed assumptions about speed and road accidents, an increase in casualties cannot be ruled out. But if there was to be an increase, it would reflect the community’s choice of trade-off. Moreover, unlike the current situation where public servants and politicians set speed limits and are blamed for any increase in casualties, there would be nobody to criticise. With choice comes responsibility.

It is high time governments stopped treating motorists like naughty children and a source of additional revenue. Australia’s speed limits are not only lower than the rest of the world, but are out of step with community values. In a society in which the government serves the people, they should be updated.