When you make a turn, merge, or change lanes, you are supposed to use your turn signal. You indicator. Your blinker. Whatever you call it, everyone knows that you’re supposed to use it. But apparently that kind of common sense knowledge has been forgotten, leaving the Supreme Court in Washington state to cast a deep, heavy sigh and remind everyone that, yes, you have to use your damn blinker.

The case arose as a result of police pulling over a drunk driver for questionable use of his turn signal, . It is quite possibly the most ridiculous case background I’ve read:

The ruling was issued in the case of David Brown, who was arrested for driving under the influence in Kennewick in March 2015. State patrol officers pulled him over after he briefly turned on his left turn signal while approaching a light in a designated left turn lane but turned it off and did not reactivate it while at the light or making the turn. He was arrested after his breath test showed .26 breath alcohol content, more than triple the legal limit.

Brown’s defense in this instance was that there was no legal basis for the traffic stop. He didn’t claim to not be driving drunk—he was arguing with the very basis of being pulled over in the first place. A lower court agreed with Brown before the case moved up to the Supreme Court.

Once there, Brown was in for a reality check. He might have used his signal to merge into the turn lane, yes—but the very fact that he had turned it off while waiting at the light and then turning meant he broke one of the very tenets of traffic law. Seriously. Here’s a post from the regarding this exact conflict:

The law regarding the use of turn signals states that any “right or left” vehicle movement must have an “appropriate signal” before proceeding. Another [sic] words, you must use your turn signal, even if you are in a right turn only lane.

You have to use your signal any time you merge, turn, change lanes, sit at a traffic light, etc. If you’re not going straight, that indicator needs to be on. Theoretically, if you’re in a dedicated turn lane, everyone should know your next move. But, just to make sure, your signal still needs to be on.

Let this be your friendly reminder not to be like David Brown. Use your common sense and rectify your lawless ways.