How many times have you heard your local newscast begin with a top story of a serious fatal car crash involving a driver who was going way too fast? This seems to happen far too frequently, and it’s these incidents that have law enforcement, public safety groups, car insurance companies, and the media itself constantly shouting the same message: speed kills, so slow down. To this end, speed limits are in place to keep us safe by regulating how fast we can legally drive our vehicles on certain stretches of roads.
But do speed limits really keep us safe? Evidence from several studies indicates something that would shock most drivers: most speed limits actually cause more accidents than they prevent.
The Logic of Speed Limits
Have you ever been frustrated by a driver on the road who is going significantly slower than the rest of the flow of traffic, sometimes by five, ten, or even twenty miles per hour? Not only do these drivers get in the way, but they’re actually a huge danger to both themselves and those around them, especially when they’re not driving in the right-hand “slow” lane.
Why is this? Simple: imagine having to pull out from behind this driver in order to get past them. On a busy road, this may involve finding a small gap in traffic to fit into and then promptly hit the gas and get up to speed with your new lane. All the while, the rest of the traffic in your lane may have to slow down in order to adjust to your entry, and thus there’s a domino effect of adjustment that significantly increases the risk of an accident. If that driver had been doing the same speed as the rest of the flow of traffic, you wouldn’t have needed to change lanes, and if you did at some point, you would already be at the appropriate speed and wouldn’t affect the traffic flow in a new lane when you do change.
In other words, speed isn’t necessarily what’s dangerous, it’s speed variance, and speed limits that are too low or too restrictive create more speed variance on roadways, thus significantly increasing the chances of an accident. Driving at slower speeds than traffic flow puts you and other drivers at danger just as much as driving much faster than other drivers.
The Parker Study
In 1997, the U.S. Department of Transportation Federal Highway Administration published a study conducted by Martin R. Parker & Associates, Inc., wherein the group chose 100 sites in 22 states all across the country and adjusted the posted speed limit. In some instances, they raised the speed limit by a few miles per hour, and in others they lowered it. Over the course of an extended period of time, the group tracked the number of car accidents in these areas and compared them with the previously-existing accident volume.
Now, if we were to assume the media, law enforcement, and car insurance companies are all correct, we could expect that the areas where the speed limit went up would see a rise in accident, and vice versa in areas where the speed limit went down. However, the results were surprising to many people: exactly the opposite happened. In areas where the speed limit went up slightly, the number of accidents went down, and areas where the speed limit became more restrictive, accident numbers went up.
The Solomon Curve
Since that time, more studies have shown that this is an effect of what’s known as the “Solomon Curve.” Essentially, the Solomon Curve shows that the overwhelming majority drivers tend to select a speed that is both safe and comfortable for the given road conditions, regardless of the posted speed limit. This is also the speed at which there are the fewest auto accidents, and a range within five miles per hour above or below this average speed also tends to be safe.
For example, near schools or in a business district with a number of crosswalks, busy sidewalks, and cars parked along the side of the road, most drivers will usually observe a slower speed limit around 25 to 30 miles per hour because it’s the safest they can reasonably travel based on those conditions—even without the speed limit being posted. However, a divided, multi-lane highway with no traffic signals or stop signs, such as a major freeway, drivers will travel 70 to 75 miles per hour on average because the conditions allow for it.
However, when this “average” speed is five or ten miles per hour above the posted speed limit, you get speed variance. There will always be that percentage of drivers who try to be good sports about road laws and follow the speed limit, no matter how slow or unreasonable they might be. After all, speeding tickets and car insurance are expensive.
However, for the rest of drivers who are simply trying to stay with the flow of traffic, those drivers present an obstacle. When a driver stuck behind that limit-follower tries to change lanes to get around them, there could be a speed difference of 10, 15, or even 20 miles per hour or more, and that causes the risk of an accident from that lane change to skyrocket!
Speed and Accident Risk Concerns Are Valid
This doesn’t mean that speed limits should be abolished: there will always be people who do place themselves and others around them at risk by driving at unreasonable speeds, and who should be ticketed for it. However, on certain roads where the speed limit is unreasonably low compared to road conditions, raising the speed limit to encourage all drivers to move at a reasonable and safe pace will improve traffic flow, result in a better driving experience, and even decrease accidents.If you’ve been hurt as a result of a car accident, call Lauri J. Goldstein & Associates, PLLC today at (866) 675-4427 to request a case evaluation!