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The Science and Politics of Bicycle Driving

Vehicles and Motor Vehicles

Figure 1: Classes of Road Vehicles Regulated by Traffic Law

Motor vehicles are a special class, or subset, of vehicle, as shown in Figure 1. Motor vehicles include cars, trucks, buses, motorcycles, and motor scooters. Non-motorized vehicles include bicycles, tricycles, and horse-drawn carriages. Traffic law in every US State either explicitly defines bicycles as vehicles or defines bicycle operators as having the rights and duties of drivers of vehicles. All vehicle operators are legally required to obey the basic Rules of the Road as described above. These rules are codified in the state laws with language such as "The driver of a vehicle shall (or shall not) do X."  However, there are some special legal restrictions for drivers of motor vehicles given the potential dangers that motor vehicles can pose to other road users and the wear and tear that motor vehicles can cause to roadways. Such laws are usually worded as "The driver of a motor vehicle shall (or shall not) do Y." The most obvious special restriction for drivers of motor vehicles is the legal requirement of an operator's license.

Many people fail to understand the distinction between rules for all vehicles and special restrictions for motor vehicles.  They may erroneously believe that if a vehicle does not have a motor, the operator is not required to obey the traffic laws for vehicles. Others erroneously believe that if the vehicle does not have a motor, the operator is not
allowed to drive it on the road according to the normal Rules of the Road. Inspection of the traffic laws in every state makes it very clear that drivers of non-motorized vehicles have the rights and responsibilities of drivers of vehicles when traveling on every public road, except in the special case of controlled access freeways with minimum speed limits that cannot be sustained by non-motorized propulsion and which do not service local destinations. This preserves bicyclists' constitutional right to access every destination served by public roads while still allowing a redundant system of expressways to be built exclusively for high-speed motor travel.