Commercial truck drivers in California and the rest of America are subject to a federal regulation whenever they are at work on the road. This rule attempts to prohibit drivers who are excessively fatigued, physically ill or otherwise temporarily incapable of operating their vehicle responsibly from going to work. However, enforcement is complicated by the lack of scientific consensus as to what fatigue is or how it should be measured.

There is no reproducible science-based test for fatigue at this moment. It is not currently possible to test an individual's blood or body to determine precisely the amount of fatigue. Researchers into the issue state that the solution may be to collect and organize more data.

Some years ago the Minnesota State Police developed a questionnaire that tried to determine the fatigue state of a driver. Incorrect answers led to a citation. However, it was eventually abandoned due to a decision that it was a violation of the Fourth Amendment prohibition against unreasonable searches.

A personal injury attorney may be of assistance to a person who has been injured in a truck accident. It may be possible to review public information such as the driver's travel log book and records of their actions during their hours off duty as well as the testimony of eyewitnesses. If it can be determined that the driver of the commercial vehicle was sleep-deprived at the time of the accident and that truck driver fatigue was the cause, then a civil lawsuit seeking compensation from both the driver and the trucking company could be successful.

Source: Overdrive Online, “Amid ‘fatigued driver' out-of-service discussions, panel releases report on research into fatigue measurement”, Todd Dills, March 10, 2016