Which 1986 U.S. law required school bus drivers to obtain a commercial driver's license?

The Commercial Motor Vehicle Safety Act of 1986 required states to establish commercial driver's licensing standards that covered school bus drivers. Congress passed the law in October 1986 after concerns about inconsistent licensing and unsafe commercial-vehicle operators.

The act created a nationwide framework for commercial driver's licenses, including vehicle classifications, testing, disqualification rules, and a central licensing-information system. Its requirements were implemented over subsequent years rather than taking effect everywhere immediately.

For a typical large U.S. school bus, a driver generally needs a CDL with passenger and school-bus endorsements. The exact license class depends on the vehicle, while smaller buses and state rules can create exceptions. The law did not itself create the yellow bus, compartmentalized seats, or every school-bus safety rule; those come from other regulations and standards.