Safer at any speed?

IT WILL be some years before cars are as smart as KITT, the talking, self-piloting car in the 1980s TV show “Knight Rider”. Several carmakers, and Google, are doing trials of self-driving cars, and Nevada has become the first American state to pass a law to regulate such trials on public roads.

Already, however, cars are increasingly coming with features that help drivers with steering and braking and, in some cases, overrule their human operators to prevent crashes. This week Ford's chairman, Bill Ford, said carmakers needed to press ahead with autonomous vehicles. He is convinced that they will ease traffic jams. And the same sorts of automation that can squeeze more cars on to the roads can also cut accidents (themselves a big cause of congestion).

Volvo's new V40 small hatchback essentially drives itself in busy traffic, maintaining a safe distance and keeping in lane without human intervention. The V40 also brakes automatically when it senses an imminent collision, as can Ford's new B-Max minivan. Such features appeared on some pricey vehicles a few years ago, but are now arriving on much cheaper models. Nissan is working on software that anticipates a driver's next move—for instance, adjusting the speed and position of the car going into a turn. This summer America's traffic-safety agency will put 3,000 test cars on Michigan's roads equipped with a variety of such “driver-assist” features.

In the short term, novel safety devices can help carmakers squeeze more profit out of buyers. But drivers soon come to expect them as standard, as do regulators. As happened with seat belts and airbags, electronic stability control—which prevents skids though automated braking—has just become compulsory for new cars in America and will be in Europe from 2014.

When this happens, such gadgetry becomes just another manufacturing cost. This week the American government postponed plans to make rear-view cameras compulsory from 2014 because carmakers are grumbling at the cost, of up to $200 a vehicle. Marcello Tamietti of Accenture, a consultancy, says electronics already account for 30% of a new car's value, and this will rise to 40% by 2020. Making all these systems work together reliably will be a growing challenge for carmakers, he says.

Another headache will be lawsuits from motorists blaming their car for crashes. Honda is already being sued in America over the collision-avoidance system on its top-end Acura models. Pim van der Jagt, a research chief at Ford, says new laws will be needed to deal with such issues—and cars may need black boxes to record what went wrong in accidents.

Volvo's aim is that by 2020 no one will ever be killed or seriously hurt driving its latest models, says its safety-research chief, Thomas Broberg. Already, new safety devices are helping to cut accidents: in 2010 traffic deaths in America were the lowest since 1949. However, there were still almost 33,000 of them, so there is a long way to go.

What of the danger that all these crash-prevention devices will lure drivers into taking more risks? Only time will tell, but at least one study shows that early anti-lock braking systems used to encourage aggressive driving. Cars are getting cleverer, but it will be years before they can make up for the stupidity of some drivers.