Drunk driving is the act of driving under the influence of alcohol. A small increase in the blood alcohol content increases the relative risk of a motor vehicle crash.
A police officer in Brisbane, Australia, conducts a random breath test on a driver.
A law enforcement grade Breathalyzer, specifically an Alco-Sensor IV
An ignition interlock device (red arrow) in a Scania bus
US poster from 1994 with the message that "drinking and driving don't mix"
Driving under the influence or driving while intoxicated is the crime of driving, operating, or being in control of a vehicle while one is impaired from doing so safely by the effect of either alcohol
1937 poster warning American drivers against drunk driving