It’s against the law to subject prisoners of war to sleep deprivation, but it happens to some truck drivers a great deal.
For inexperienced drivers, sleepiness can be the biggest of several problems with night driving. On the other hand, for drivers who’ve learned how to drive at night, sundown is often a welcome sight.
Federal Motor Carrier Safety Regulations (FMCSR
"Until a formal regulation is established with clear guidelines and borders ...