Without the details of how crashes happen, we tend to dismiss them as the work of “idiots”—drivers who occupy the lower echelons of driving skill and common sense. But while humankind’s measured intelligence is increasing, so is the number of deadly car crashes. After a lifetime of improvement, we saw an 8 percent jump in crash fatalities during 2015, the largest in 50 years. That number rose again in 2016, when more than 40,000 people died in collisions.

Fortunately, science is coming to the rescue. We no longer have to rely solely on dents, skid marks, and the lawyer-vetted remarks of drivers to figure out what happened and to tell us how to avoid the next crash. In a landmark study published in 2008, researchers at the University of Michigan combed the scene of 6,950 crashes to give us a more detailed analysis of what happened during each crash. Naturalistic driving studies are now equipping cars with accelerometers, sonar, sensors that track driver inputs, and lots of video cameras. Drivers sign up to participate in these studies, and they sometimes crash, leaving researchers with valuable data. We’re also benefiting from the rise of road cams—dashboard-mounted video cameras owned by everyday drivers, aka cammers, who cruise around, record crashes, and then post them on websites like Reddit.