Being drowsy or “half asleep” impairs your road sense.

Drinking is probably the biggest and most heavily stressed “do not” when it comes to driving, and most people would never even consider sleep to have a negative correlation with driving, yet new data tells us otherwise!
If an average person gets less than six hours of sleep in a night they begin to have a slower reaction time, diminished coordination, and impaired judgment. This correlates to driving because it makes it more difficult to navigate a car when a person’s brain is not operation at it’s full potential.
The legal limit for drinking and driving in most of Europe is a BAC of .05, which is about how impaired your brain is after not sleeping for 17 hours! Although America is slightly higher, usually around .08 or .1, scientists still acknowledge the dangers of not sleeping and operating a car.
People who commonly work night shifts are especially at risk because they usually sleep a couple hours less and at awkward hours, making driving sober with little sleep more dangerous than being slightly intoxicated!