National Maximum Speed Law

As an emergency response to the 1973 oil crisis, on November 26, 1973, President Richard Nixon proposed a national 50 mph (80 km/h) speed limit for passenger vehicles and a 55 mph (89 km/h) speed limit for trucks and buses. In response to Nixon's proposal, the National Maximum Speed Limit (NMSL) was enacted in the 1974 Emergency Highway Energy Conservation Act that withheld Federal Highway funds from States that refused to comply with provisions of the law, including a maximum speed limit of 55 miles per hour (89 km/h) for passenger vehicles, an increase Nixon approved in signing the final legislation.

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