Driving While Sleepy – Is It Legal?

Driving when feeling sleepy is dangerous, as dangerous as other types of illegal driving.

A large percentage of adult’s experience insomnia and other sleep disorders that cause sleep deprivation. There are two types of sleep deprivation. One occurs when someone is completely deprived of sleep. The other is when there is cumulative sleep debt. Sleep debt occurs when an individual doesn’t get the sleep they need. Repeatedly getting too little sleep creates an accumulated sleep debt that is often more dangerous than sleep deprivation from not sleeping at all.

driving while sleepy


The biggest reason total sleep deprivation is not as dangerous as cumulative sleep deprivation is that individuals who are experiencing total sleep deprivation feels the lack of sleep acutely. Their awareness of being overly tired helps them make better decisions, such as allowing someone else to drive or choosing to delay travel until they are rested.

Total sleep deprivation causes impairments that are equivalent to a blood alcohol level of .1 in just 24 hours. The legal limit for alcohol is .08. Longer periods of sleep deprivation cause dizziness, disorientation, and even hallucinations when sleep deprivation extends to several days.


Partial sleep deprivation is the more dangerous form of sleep deprivation when it comes to driving while sleepy because chronic sleep deprivation makes our sleep deprived state feel normal. In other words, we become as impaired as someone who is legally drunk, but we feel normal. As a result, we don’t take the same precautions we use when we are aware that we are suffering from sleep deprivation.


Driving when feeling sleepy isn’t illegal. The reason is tied to enforcement difficulties. A breathalyzer or blood test can be used to determine whether someone is legally drunk, but there isn’t an equivalent test to verify that someone was too sleepy to drive safely.

Other legal problems can arise as the result of driving when you are impaired as the result of sleep deprivation. Sleep deprivation impairs cognitive function and makes us perceive our experiences as more threatening. This increases the risk we’ll experience road rage, which is illegal.

Sleep deprivation can cause episodes of microsleep that lead to distracted driving that can be reckless, which is another source of legal problems tied to sleep deprivation.


sleepy drivingThe dangers associated with driving while sleep deprived expand beyond reckless driving. Serious accidents including Three Mile Island, the Exxon Valdez, and the Challenger disaster were all tied to sleep deprivation.

Sleep deprivation reduces cognitive performance, which can lead to poor judgment. A good personal injury lawyer can often prove that a driver was driving when they knew they were sleep deprived using statements they made to witnesses about being tired or by documenting job responsibilities that didn’t allow them enough time to sleep.


The Center for Disease Control (CDC) issued a warning that 1/3 of Americans experience sleep deprivation. Individuals who suffer from anxiety, depression, new parents, people with too many responsibilities for the time they have available and individuals who are addicted to video games or binge-watching shows are at risk.


The danger of driving when feeling sleepy is real. There are a variety of ways to avoid driving when it is ill-advised due to sleep deprivation. Giving sleep the priority it deserves is the first step because being rested eliminates the risk sleep deprivation will impair your driving.

Be creative and don’t be afraid to ask for help when you need to travel when you’re sleep deprived. Use public transportation, Uber, Lyft, or ask friends for assistance. Don’t plan trips that will impair your ability to sleep enough to be safe. If you feel sleepy, pull over and take a nap or get a hotel and sleep.

Don’t rely on methods such as turning the radio up loud, opening the window, putting the air conditioner on high, or eating. They are not effective.

No trip is worth taking the risks involved in driving when you are impaired by sleep deprivation. Be aware of how tired you are and adjust your plans when you are sleepy.