Imagine a cure for cervical cancer was discovered. In Ontario, 140 lives a year would be saved. That’s about the decline in highway traffic deaths in Ontario over the past two years—a 32 per cent drop from 453 in 2007 to 310 last year. What happened? Experts debate the causes. But police measures seem to be a major direct factor. Ontario has a new anti-street-racing law that allowed cops to hand out 10,000 seven-day suspensions. Speed-related fatalities dropped nearly 50 per cent from ’07 to ’09. And Ontario Provincial Police credit their own strategies, such as mining traffic data more effectively to make sure police cars are visible around accident hot-spots. Whatever’s working, it’s hard to think of any short-term public-policy shift that’s saving as many lives.