So what am I suggesting—abolishing signs and rules? A traffic free-for-all? Actually, I wouldn’t be the first to suggest that. A few European towns and neighborhoods—Drachten in Holland, fashionable Kensington High Street in London, Prince Charles’s village of Poundbury, and a few others—have even gone ahead and tried it. They’ve taken the apparently drastic step of eliminating traffic control more or less completely in a few high-traffic and pedestrian-dense areas. The intention is to create environments in which everyone is more focused, more cautious, and more considerate. Stop signs, stoplights, even sidewalks are mostly gone. The results, by all accounts, have been excellent: pedestrian accidents have been reduced by 40 percent or more in some places, and traffic flows no more slowly than before.
What I propose is more modest: the adoption of something like the British traffic system, which is free of many of the problems that plague American roads. One British alternative to the stop sign is just a dashed line on the pavement, right in front of the driver. It actually means “yield,” not “stop”; it tells the driver which road has the right of way. Another alternative is the roundabout. Roundabouts in the U.S. are typically large. But as drivers get used to them—as they have in the U.K. over the past three or four decades—they can be made smaller and smaller. A “mini-roundabout” in the U.K. is essentially just a large white dot in the middle of the intersection. In this form, it amounts to no more than an instruction to give way to traffic coming from the right (that would be the left over here, of course, since the Brits drive on the left).
As these examples indicate, traffic signs in the U.K. are often on the road itself, where the driver should be looking. And most right-of-way signs are informational: there are almost no mandatory stops in the U.K. (The dominant motive in the U.S. traffic-control community seems to be distrust, and policies are usually designed to control drivers and reduce their discretion. The British system puts more responsibility on the drivers themselves.)
Speed limits in the U.K. are also simpler and better. They are set by road type, so drivers know what limits to expect on highways, rural roads, and urban roads—usually without any signs to tell them. These limits are relatively high, set assuming optimum driving conditions, in contrast to the U.S. limits, which seem to be set with something in between the best and worst conditions in mind. (Precisely where on this spectrum U.S. limits fall seems to vary from road to road, engendering mistrust of the signs in some drivers.) Nonstandard speed limits in the U.K. are rare, so you tend to take them quite seriously when they appear, and they are posted frequently—so you don’t risk missing them if you’re, say, watching the road ahead of you.
I’ve given several talks on traffic in the U.S. and have always found members of the audience to be highly skeptical that the U.K. traffic system could possibly be safer than the one on this side of the Atlantic. As noted, there seem to be more fender benders over here. But not all minor accidents get reported to the police, in either country, and definitions vary. So let’s look at fatalities: everyone agrees on what death is, and fatalities are always reported.
Detailed statistics show that as of 2003, fatalities per mile traveled were 36 percent greater in the U.S. than they were in the U.K. Traffic deaths per million people show an even greater disparity through 2006, the most recent year for which full statistics are available. If the U.S. death rate were the same as the U.K.’s, roughly 6,000 fewer Americans would die each year—that’s half again as many Americans as have died in Iraq in the past five years.
As experimentalists like to remind us, correlation isn’t causation, and differences in traffic-control policies might not be the only reason for this huge difference in traffic deaths. Perhaps people drive slower in Britain? Well, no; in my experience, they usually drive faster. Are cars themselves safer in Britain? Again, probably not; they tend to be smaller, with fewer safety features. It is true that SUVs are more prevalent in the U.S., and that SUVs are often lethal when they hit smaller cars; this likely accounts for some of the difference in fatality rates. But it’s also true, for instance, that when traditional intersections in the U.S. have been replaced by roundabouts, collisions have typically been reduced by about 40 percent, and fatalities by up to 90 percent. And as the U.K. has refined and simplified its traffic-control system over the past 30 years, total traffic fatalities have fallen by about 50 percent. Over the same period, fatalities in the U.S. have declined by just 20 percent; in the past several years, they haven’t declined at all.
Conjurers and magicians have long known how to distract people so they miss a move that should be obvious. But it is only recently that social psychologists have come up with dramatic demonstrations of just how tight the limits on our attention can be. One of the most compelling is a 75-second video, by the psychologists Daniel Simons and Christopher Chabris, that shows six male and female students, in black or white T-shirts, passing basketballs to one another. The observer is asked to count the number of passes.
About 45 seconds in, a person in a gorilla suit walks onscreen. She strolls between passers to the center of the screen, faces the camera, beats her chest, and then exits. You can’t possibly miss her—unless, that is, you’ve been instructed to pay attention to the basketballs. When each observer in the experiment was asked, “Did you notice anything unusual in the video?” about half said no. That’s inattentional blindness, the effect of competition for the observer’s attention: by looking for one thing, we miss another that should have been obvious.
The miseducation that U.S. drivers are receiving is not as explicit as the instructions to these students, but it extends over years and is in some ways more forceful: the legal penalties for failing to notice traffic signs are severe. I believe that U.S. traffic policies are inducing a form of inattentional blindness in American drivers. When so many drivers say, after an accident, “I didn’t see him,” they’re not all lying.