I remember as a young driver being told that it always was improper to pass another car on the right unless there were two marked lanes in the same direction. As far as I can tell, this never was the law in Arizona. It appears to be a popular long-standing myth regarding our traffic-control laws.
In most cases, it is legal to pass another car on the right, as long as you do not leave the pavement or main traveled portion of the roadway.
Arizona Revised Statutes section 28-724 sets out the circumstances under which it is permissible to pass on the right:
- When the vehicle you are passing is making a left turn or is about to make one
- When there is enough unobstructed pavement for at least two lines of vehicles to move in each direction
- On one-way streets, when the road is unobstructed and wide enough for at least two lines of vehicles
In no case may a driver pass another vehicle on the right unless the movement can be made safely. Never risk personal injury to yourself or others.
It always is improper to pass a stopped school bus—on the left, right or from any direction—if the bus is displaying a stop sign and flashing lights. It also is unlawful to pass another vehicle in posted "no passing" zones.
Generally, however, as long as you can pass safely without leaving the pavement, you legally may pass another vehicle on the right.
Slow-moving vehicles are required to drive as near as practical to the right side of the road. However, this probably is the most commonly violated rule of the road in Arizona. Obviously, the rule does not apply when a driver is preparing to make a left turn.
Our law permitting passing on the right side of another vehicle is intended to keep traffic moving efficiently. In reality, however, it must be recognized that passing on the right, although permitted, may increase the risk of an accident and injuries. If drivers would adhere to the rule that slow traffic should stay as far to the right as practical, others would not be left with the temptation to pass on the right.
The underlying theme of all traffic laws is that all movements be made with safety or not at all. It often may make more sense to bypass the right to pass on the right.