Why Do Speed Limits Feel So Wrong Sometimes?
Ever cruised down a street and thought, “Why is the speed limit so low here?” Or maybe you’ve zipped along a wide, empty road and wondered why the sign says 35 when everyone’s doing 50. You’re not imagining things—there’s a reason speed limits often seem out of sync with reality. For decades, most states have relied on something called the 85 percent rule to set those numbers. But as crash rates and community complaints pile up, that old formula is under fire—and for good reason.
What Exactly Is the 85 Percent Rule, and Why Is It Controversial?
Here’s how it works: traffic engineers measure how fast cars naturally go when the road is clear. They find the speed at or below which 85 percent of drivers travel, then round it to the nearest five miles per hour. The idea? Most people drive at a speed they feel is safe, so the majority must be right. Simple, right?
Not so fast. Critics say this approach is outdated and dangerous. Why? Because it creates a feedback loop: as drivers push the limits, the “safe” speed creeps up, and so does the official limit. The result? Streets that get faster and, according to safety advocates, more hazardous for everyone—especially pedestrians and cyclists. A 2022 study in the journal Accident Analysis & Prevention found that raising speed limits in line with the 85 percent rule led to higher crash rates, particularly in urban areas with lots of foot traffic.
Are Cities and States Changing How They Set Speed Limits?
Absolutely. The federal government recently clarified that the 85 percent number was never meant to be a hard-and-fast rule. Instead, they now urge states to consider crash data, land use, and the presence of pedestrians when setting limits. Some cities are already ahead of the curve.
Take Madison, Wisconsin, for example. Their “20 is Plenty” campaign dropped residential speed limits from 25 mph to 20. Seattle made a similar move and saw a noticeable drop in serious injuries—proof that a lower number can make a real difference. Ohio now lets cities use the 50th percentile speed (the speed at which half of drivers go slower and half go faster) for busy pedestrian areas, which often results in lower limits.
But it’s not always a slam dunk. Boulder, Colorado, tried lowering limits, but a recent city report found it didn’t do much to slow drivers down. Turns out, there’s more to the story than just changing the sign.
Does Street Design Matter More Than the Speed Limit?
Here’s where things get interesting. Many driver advocates argue that the design of the road itself has a bigger impact on speed than any number on a sign. Wide lanes, gentle curves, and long sightlines practically beg drivers to go faster. Narrow lanes, sharp turns, and lots of visible pedestrian activity? Those naturally slow people down.
Jay Beeber from the National Motorists Association puts it bluntly: “It doesn’t really matter what number you put on a sign. The average driver drives the nature of the roadway.” And he’s got a point. If a road is built for speed, people will drive fast—no matter what the sign says. In fact, a 2023 report from the Insurance Institute for Highway Safety found that redesigning streets to include narrower lanes, curb extensions, and more crosswalks was far more effective at reducing speeds than simply lowering the posted limit.
How Are Safety Advocates and Lawmakers Responding?
There’s a growing push to rethink not just speed limits, but the roads themselves. Safety groups like the National Highway Traffic Safety Administration (NHTSA) are calling for context-based approaches—think about who uses the street, what’s nearby, and how crashes happen. Some states are even experimenting with “self-enforcing” streets, where the design itself encourages safer speeds. It’s a shift from blaming drivers to reimagining the environment they drive in.
Still, change is slow. Many states stick with the old system because it’s simple, predictable, and—let’s be honest—less controversial with drivers. But as more cities see success with safety-first strategies, the momentum is clearly shifting.
What’s the Real Secret to Safer Streets?
Here’s the bottom line: setting safer speed limits isn’t just about picking a number. It’s about understanding how people actually use the road, what the street looks like, and who’s at risk. Lowering limits can help, especially in neighborhoods and busy pedestrian zones. But if the road feels like a racetrack, drivers will treat it like one.
The big takeaway? Safer streets aren’t about perfection—they’re about smarter adjustments. Start with one change this week, and you’ll likely spot the difference by month’s end. Sometimes, it’s not the sign that needs fixing—it’s the street itself.