Rules of the Road

If you’re annoyed at drivers going under the speed limit, the problem isn’t them, it’s you

Washington law states that once five or more cars have formed a line behind the slower driver, the driver is required to pull off the roadway at the earliest safe opportunity to let the following cars pass.
Washington law states that once five or more cars have formed a line behind the slower driver, the driver is required to pull off the roadway at the earliest safe opportunity to let the following cars pass. Getty Images

Question: When the freeway speed is 60 mph, may I drive 50 mph in far right lane with an RV? What is slowest speed allowed without getting ticketed?

Answer: This is a new twist on speed questions. Usually people ask how fast they can go without getting a ticket. Most roads don’t have an official minimum speed limit, but we do have a couple of laws that address driving at speeds slower than the posted speed limit. I’d like to point out that the posted speed limit is the maximum speed allowed, so technically, all drivers should be driving at or below the speed limit. If you’re getting annoyed following someone who is driving at or a mile or two per hour under the speed limit, the problem isn’t them, it’s you.

As to how much slower than the speed limit you can travel, here’s what the law says: “No person shall drive a motor vehicle at such a slow speed as to impede the normal and reasonable movement of traffic except when reduced speed is necessary for safe operation or in compliance with the law.” The question becomes, “What is normal and reasonable?”

On a road with a single lane in each direction, ten miles per hour below the posted speed limit might impede the “normal and reasonable movement of traffic,” especially if the driver remained in that lane for an extended period of time. In that situation, the law states that once five or more cars have formed a line behind the slower driver, the driver is required to pull off the roadway at the earliest safe opportunity to let the following cars pass. I should point out that the requirement for slower vehicles doesn’t include a number of miles per hour under the speed limit; it again uses the “normal flow of traffic” kind of language, so even if you’re pretty close to the speed limit, if five or more cars are backed up behind you, the law requires you to pull over to let them pass.

On a non-law related note, if you check your rearview mirror as often as you should, seeing five cars behind you, all ready to pass at the next opportunity, probably creates some anxiety that’s making your drive less enjoyable than it should be. Pulling over takes a minute, but it also releases some driving stress. It’s probably a worthwhile trade.

On the freeway, I’m reasonably confident that driving ten miles per hour under the speed limit wouldn’t be a problem. With multiple lanes, other drivers can easily pass you. Also, in Washington our 70 mph freeway zones have a posted 60 mph speed for trucks. Clearly the state doesn’t see a 10 mph speed differential as a problem. If you’re not impeding the normal flow of traffic and you’re not creating a hazard, I don’t expect you’d get a ticket for driving too slow.

However, speed differential can be a problem on the freeway. We know speed is a factor in the seriousness of a crash; faster collisions result in more damage and injury. It’s physics. But going slow on a higher-speed roadway can increase the risk of a crash. We expect other drivers to travel at speeds somewhere near the speed limit, so driving at a significantly slower speed would surprise other drivers. And one of the ways of defining a successful commute is that there were no surprises.

Although it’s uncommon, some roads can have posted minimum speed limits. If you were to drive at a speed below the posted minimum, you could get a ticket for driving too slow.

I’ll point out that all the laws about minimum speeds have a provision for driving slower than normal for safety reasons. If there’s a hazard in the road or weather conditions demand slower speeds, drive at the speed that keeps you safe. Don’t let the pressure of other drivers push you to drive at a speed that results in taking undue risk. I recall getting caught in an unexpected snow storm on I-5, where visibility and icy conditions limited speeds to about 30 mph even though the posted speed limit is 70 mph. I was passed by several vehicles on my drive that I later passed because they had slid off the roadway.

Road Rules is a regular column on road laws, safe driving habits and general police practices. Doug Dahl is the Target Zero Manager for the Whatcom County Traffic Safety Task Force. Target Zero is Washington’s vision to reduce traffic fatalities and serious injuries to zero by 2030. For more traffic safety information visit TheWiseDrive.com. Ask a question.

  Comments