From today’s “I didn’t know that” file: motorcycles are legal in HOV lanes in all 50 states. The Federal Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991, which provided for HOV lanes, requires any state that wants to ban motorcycle use of HOVs to certify that motorcycles present a hazard in HOV lanes. According to NHTSA, motorcycles are actually slightly safer in HOV lanes than regular vehicles are.
Apparently ISTEA also calls for restricting HOV use to vehicles that are at 50% or more of carrying capacity, e.g. a one-person motorcycle is at 100% capacity, as is a Miata with two people in it. However, if two people are in my seven-passenger minivan, that’s apparently still OK with most states— go figure.
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