The study found no tangible difference in accident rates between the ABS-equipped cars and the remainder. But one difference was statistically significant: driving behavior. The drivers of the ABS-equipped cars became far more reckless. They tailgated more often. Their turns were sharper. They drove faster. They switched lanes dangerously. They were involved in more near misses. Paradoxically, a measure introduced to boost safety promoted unsafe driving behavior.77
The psychologist Gerald Wilde calls this phenomenon risk homeostasis.75 The phrase is fancy, but the idea is simple. Measures intended to decrease risk sometimes backfire. Humans compensate for the reduced risk in one area by increasing risk in another.