In the state of Washington, you are allowed to turn left on a red light onto a one-way street

A little-known quirk of the driving laws in the state of Washington is that, after coming to a complete stop, you are allowed to turn left on a red light onto a one-way street.

• Are left turns on red arrows legal?
• Left turn is legal, but be careful.
• When to turn left on red lights
• Are left turns onto one-way streets allowed at red lights?

Note the requirement that the destination street be a one-way street. A left turn against a red light onto a two-way street is not allowed.

What is even less well-known is that a one-way freeway onramp is considered a one-way street.

The opportunities to take advantage of this rule do not often arise because there is usually enough conflicting traffic (both vehicular and pedestrian) that you cannot safely execute the turn. But one place where it becomes useful is near Microsoft main campus: If you’re traveling eastbound on NE 40th Street and wishing to turn left to enter state route 520.

When waiting for the green left arrow, you can encounter the situation where non-turning traffic has a green light, which means that there can be no inbound traffic from the right hand side. (Doubly so because they also have a “No turn on red” sign, so not only can they not go straight or left, they can’t even turn right.) This means that the only sources of conflicting traffic are oncoming traffic and pedestrians crossing the onramp.

Checking for pedestrians is easy because pedestrians don’t move that fast, and there is not very much pedestrian traffic on that side of the street anyway. Oncoming traffic is easy to to check because you’re looking right at them. Furthermore, the traffic light at the intersection of NE 40th Street and 156th Ave NE meters the oncoming traffic, so when that light turns red, the oncoming traffic often vanishes, which means that you have a huge gap in which to make your left turn.

Note that the state of Washington is unusual in permitting a left turn on a red light from a two-way street to a one-way street. Most states limit this to the case where you are turning from a one-way street to a one-way street.