Safety Numbers on Autonomous Cars Just Don't Add Up

The "Race to Autonomy" has become the high-tech competition of our time, pitting automakers, suppliers, technology titans and Silicon Valley startups against each other in intense competition for the first bite of what will be a trillion-dollar driverless vehicle business. This horse race between some of the biggest companies in the world makes for gripping entertainment, but there is mounting evidence that it does so at the cost of important long-term perspective.

The California Department of Motor Vehicles has released its annual "disengagement reports" documenting each time a human "safety driver" had to take control of an autonomous test vehicle on the state's roads. Once again, the reported numbers are being widely used by the media to handicap the competition. This is understandable given how little data are publicly available. But any temptation to take these disengagement numbers as an apples-to-apples comparison between makers should be resisted.