My wife has an mercifully short commute to work, which most days she speeds up by biking there. Friday morning, that route led to a detour through an X-ray machine and a CT scanner.

The fault: an idiot driver who attempted to make a left turn from a center, no-turn lane by signaling late and then turning into my wife’s path. She braked hard, fell off the bike and landed on her shoulder. The resulting damage: a fractured clavicle bone and some scrapes, plus a few weeks of having to get through everyday chores with her left arm in a sling.

The driver, meanwhile, continued on. It’s unclear whether passerby will be able to identify this menace.

At one level, I’m angry to see this reckless disregard for any human beyond one’s own windshield, much less my spouse. A driver like that could also threaten me when I’m walking around the neighborhood, or my neighbors, or any of our kids.

At another level, I don’t know why this happened to my wife and not me. She is an exceptionally careful cyclist–she was wearing a reflective vest Friday, just in case–while I have been much more foolish, especially in my younger days. (If I blew by you going the opposite way on the W&OD Trail or the Cap Crescent 15 or 20 years ago, I’m sorry; I was a jackass.) And I’ve clocked several thousand more miles on two wheels. By that statistic alone, I should have taken this hit, not her.

What I do know: If you can’t share the road, do the rest of us a favor and get off the road until you can strap yourself into a self-driving car that, unlike you, will at least be programmed to obey the laws of the U.S. and the laws of physics.