Seat belt legislation in the United States

Most seat belt laws in the United States are left to the states. However, the first seat belt law was a federal law, Title 49 of the United States Code, Chapter 301, Motor Vehicle Safety Standard, which took effect on January 1, 1968, that required all vehicles (except buses) to be fitted with seat belts in all designated seating positions. This law has since been modified to require three-point seat belts in outboard-seating positions, and finally three-point seat belts in all seating positions. Initially, seat belt use was not compulsory. New York was the first state to pass a law which required vehicle occupants to wear seat belts, a law that came into effect on December 1, 1984.

U.S. seatbelt laws may be subject to primary enforcement or secondary enforcement. Primary enforcement allows a police officer to stop and ticket a driver if he or she observes a violation. Secondary enforcement means that a police officer may only stop or cite a driver for a seatbelt violation if the driver committed another primary violation (such as speeding, running a stop sign, etc.) at the same time. New Hampshire is the only U.S. state that does not by law require adult drivers to wear safety belts while operating a motor vehicle.

In 18 of the 50 states, the seat belt law is considered a secondary offense, which means that a police officer cannot stop and ticket a driver for the sole offense of not wearing a seatbelt. (One exception to this is Colorado, where children not properly restrained is a primary offense and brings a much larger fine.) If a driver commits a primary violation (e.g., for speeding) he may additionally be charged for not wearing a seatbelt. In most states the seat belt law was originally a secondary offense; in many it was later changed to a primary offense: California was the first state to do this, in 1993. Of the 30 with primary seat belt laws, all but 8, Connecticut, Hawaii, Iowa, New Mexico, New York, North Carolina, Oregon, and Texas, originally had only secondary enforcement laws.

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