Fatigued driving, also known as drowsy driving, occurs when a driver operates a vehicle while experiencing significant tiredness or exhaustion that impairs their ability to drive safely. This condition can result from lack of sleep, long work hours, untreated sleep disorders, medication side effects, or extended periods of driving without adequate rest breaks. The effects of driver fatigue are remarkably similar to those of alcohol impairment—studies show that being awake for 18 hours straight produces impairment equivalent to a blood alcohol concentration of 0.05%, while 24 hours without sleep is comparable to a BAC of 0.10%, which exceeds California's legal limit of 0.08%.
The dangers of fatigued driving extend beyond simple tiredness. When drivers are exhausted, they experience microsleeps—brief episodes lasting just a few seconds where they essentially lose consciousness. At highway speeds, a vehicle can travel the length of a football field during a 3-4 second microsleep, making these episodes extremely dangerous. Additionally, fatigued drivers exhibit slower reaction times, reduced attention to road conditions, impaired decision-making abilities, and decreased awareness of their surroundings. These impairments significantly increase the likelihood of causing rear-end collisions, lane departure accidents, head-on crashes, and single-vehicle accidents.
Certain groups face higher risks of fatigued driving accidents. Commercial truck drivers who spend long hours on the road, shift workers who drive home after overnight shifts, medical professionals working extended shifts, young drivers aged 16-25, and individuals with untreated sleep disorders like sleep apnea are all at elevated risk. California has specific regulations governing commercial drivers' hours of service to address this issue, but enforcement challenges and violations remain common. Understanding these risk factors helps identify when driver fatigue may have contributed to an accident and strengthens your legal claim.