The Economics of Road Safety

How economists value lives saved on roads, why safety rules can change behaviour, and what measures reduce deaths most cost-effectively.

The World Health Organization estimates that around 1.2 million people die in road crashes every year, and many millions more are injured. Road crashes are a leading cause of death for young people worldwide. Economists help governments decide how much to spend on safety and which measures save the most lives per dollar.

Valuing a statistical life

To compare safety spending with its benefits, governments use the value of a statistical life. This does not put a price on any particular person. It is based on how much people are willing to pay for small reductions in risk.

If each of 100,000 people would pay 100 dollars to reduce their risk of dying by 1 in 100,000, together they would pay 10 million dollars to prevent one expected death. That 10 million dollars is the value of a statistical life. U.S. government agencies have used values above 10 million dollars in recent years. Other countries use different values.

Risk compensation

Safety measures can change behaviour. In 1975, economist Sam Peltzman argued that drivers who felt safer because of mandatory safety features might drive more aggressively, offsetting some of the benefit, particularly for pedestrians. This is called risk compensation. Later research has generally found that safety measures like seatbelts still save many lives overall, though behaviour can reduce the gains somewhat.

What works

Measures with strong evidence include:

Seatbelt and helmet laws with real enforcement.
Lower speed limits in towns, since the risk of death for a pedestrian rises steeply with vehicle speed.
Drink-driving laws and random breath testing.
Safer road design, such as roundabouts, separated lanes and safe crossings.

Helmets for two-wheelers

In countries such as India, where two-wheelers make up a large share of vehicles, helmet use is one of the most cost-effective safety measures. A helmet costs little, yet studies find proper helmet use greatly reduces the risk of death and serious head injury in a crash. Enforcing helmet laws can save many lives for very little public spending.

Why roads are especially risky for some

Pedestrians, cyclists and motorcyclists account for over half of road deaths globally, according to the WHO. Safer crossings, sidewalks and speed control benefit these groups most, including blind and visually impaired pedestrians, for whom predictable crossings with audible signals are essential.

Thinking valuing lives is heartless

The value of a statistical life is not a statement that a life is worth a set amount of money. It is a tool for making sure limited budgets are spent where they prevent the most deaths. Without it, governments might spend heavily on one safety measure while ignoring cheaper ones that would save more lives.

Key takeaways

Around 1.2 million people die in road crashes each year, according to the WHO.
The value of a statistical life is based on what people pay for small reductions in risk.
Risk compensation can reduce, but usually does not erase, the gains from safety rules.
Helmets, seatbelts, lower urban speeds and safer road design save many lives cost-effectively.