In spite of what the law says, it’s best to stay in your own lane in an intersection

Vehicles turn left at the intersection of Cornwall Avenue and Alabama Street. Washington state laws may not prohibit changing lanes in an intersection, but police highly recommend against it for safety.
Vehicles turn left at the intersection of Cornwall Avenue and Alabama Street. Washington state laws may not prohibit changing lanes in an intersection, but police highly recommend against it for safety. The Bellingham Herald file

Question: I have a question about the rule about changing lanes when going through an intersection. I see a lot of drivers change lanes when making a right or left turn going through an intersection. Is that legal?

Answer: At a minimum, changing lanes while turning through an intersection is sloppy driving. It might also be lazy driving; instead of making the effort to complete two separate maneuvers (driving through the intersection and then changing lanes) the driver is rolling it all into one.

Some might call that efficient, but I stand by my word choice from the beginning of the previous sentence.

I’m willing to state that it’s unpredictable as well. We expect cars to stay in their lanes as they drive through intersections. Why? Because that’s what we’ve been taught, which is why I was confident that I could find support from the Revised Code of Washington to show that it’s also against the law.

Turns out, that’s tougher than it sounds. I’ll get to that in a bit.

I made the claim that we’ve been taught to stay in our lanes in an intersection. I began to second guess myself, wondering if maybe drivers change lanes in intersections because they actually don’t know better. I checked the Washington Driver Guide, because it contains the absolute minimum you need to know to drive safely.

I’d argue that the Driver Guide by itself is insufficient and that every driver should be required to take a driver education class before getting a license, but that’s an argument for another day.

As it turns out, even if a driver never spends one minute in a driver training class and passes the driver test using only the Washington Driver Guide as a resource, that driver should reach the conclusion, based on the Driver Guide, that it’s illegal to change lanes in an intersection, at least while turning.

To quote the guide, “Turn from the lane that is closest to the direction you want to go and turn into the lane closest to the one you came from ... without crossing lane lines.” And, “If there are signs or lane markings that allow for two or more turning lanes, stay in your lane during the turn.” Finally, “Once you have completed your turn, you can change to another lane if you need to.” Case closed, right?

I wish it was that easy.

I searched the RCW for a law that said something like, “It is illegal to change lanes in an intersection.” Of course, being a legal text, I expected it to take a lot more words to say the same thing. Instead, I came up a little short of my expectations.

The law about lane changes (RCW 46.61.140) states that a vehicle shall not change lanes until the driver has determined that it can be done safely; it doesn’t mention anything about intersections.

The law about turning in intersections (RCW 46.61.290) states that drivers should stay in their lane whenever “practicable.”

At least I was getting closer to an absolute prohibition, but it did suggest that there are at least some scenarios where you could change lanes in a turn. When is it not “practicable” to stay in your lane? Only in emergencies? Or on a road with multiple lanes in the same direction, if the lane you’re headed for is too full of cars to allow you to complete the turn, could you switch lanes in the intersection to get into an emptier lane and complete the turn instead of waiting for your lane to clear and possibly miss the green light?

This all seemed too wishy-washy for me. I thought the law would clearly prohibit lane changes in intersections.

Just to make sure I understood the law correctly, I called a few police officers and deputies to get their take. They all confirmed that the law doesn’t entirely prohibit lane changes in intersections, but every one of them added that in nearly all situations it’s a bad idea, and can still be illegal.

How? It goes back to that law about the requirement for lane changes to be done safely. As one officer told me, there’s usually too much stuff going on in an intersection to make a safe lane change. The law puts the primary responsibility for safety on the lane-changer and, if the lane change results in a crash, the person changing lanes would most likely be the one found at fault for the crash.

So why does the Driver Guide instruct us to always stay in our lanes while turning in an intersection? Maybe it was just an over-simplification of the law. Or maybe it’s because, required or not, it’s good advice.

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Doug Dahl, Target Zero Manager for the Whatcom County Traffic Safety Task Force, answers questions about road laws, safe driving habits and general police practices every Monday. Ask him a question using our form. Target Zero is Washington’s vision to reduce traffic fatalities and serious injuries to zero by 2030. For more traffic safety information visit