DC Traffic Laws: Speed, Right-of-Way, and Intersections
Traffic laws is the domain that tests whether you can apply the District's rules of the road, not just recall them. Expect questions on speed limits, right-of-way, signals, lane use, school buses, and impaired driving. The exam often combines two rules in one scenario, so learn which rule controls when they overlap.
Speed, lanes, and signals
Unless a sign says otherwise, the DC speed limit is 25 mph. Slow below the posted limit when conditions demand it. Keep right except when passing or preparing for a left turn. Signal every lane change and turn early enough to give others time to react. DC's move-over law requires you to change lanes or slow down for emergency and roadside vehicles with flashing lights.
Right-of-way and intersections
At a four-way stop, the first vehicle to stop goes first. If two arrive at the same time, the vehicle on the right has the right-of-way. A vehicle turning left must yield to oncoming traffic going straight or turning right. At a red light, you may turn right after a full stop and yield, unless a sign prohibits it. Pedestrians in a crosswalk have the right-of-way.
School buses and impaired driving
Stop for a school bus with flashing red lights on an undivided road. On a divided highway, traffic in the opposite direction does not have to stop. Driving with a BAC of 0.08 or higher is illegal for adults; under-21 drivers face zero-tolerance penalties.
Worked example
You and an oncoming car stop at the same time at a four-way stop. You want to turn left; the other driver is going straight. Who goes? The other driver. At a simultaneous stop, the straight-through vehicle has priority over the left-turning vehicle, and a left turn must yield to oncoming traffic. You wait until the other car clears the intersection, then turn.
Traps that cost marks
Do not assume a green light means go without yielding to pedestrians or vehicles still in the intersection. Do not treat right-on-red as automatic; it requires a stop and yield and may be banned by sign. Do not pass a stopped school bus on an undivided road. Do not confuse the 25 mph default with a safe speed in rain or fog.