Drunk Driving Exams
The testing is conducted by instructors at a driving school. First, the instructors ride in cars driven by participants and assess the participants’ driving abilities while sober. After the participants consume enough alcohol to be over the ‘legal limit’, the instructors ride in cars with them and evaluate their driving skills while ‘under the influence’.
A police spokesperson said the purpose of the program is for drivers to, “get a sense of how dangerous drunk driving can be”. Some participants said the driving tests showed them they were overconfident in their ability to drive under the influence but came to realize alcohol affected their ability to control the vehicle. The police spokesperson said, “We hope that more drivers will realize how dangerous drunk driving is”.
Why Drunk Driving is Dangerous
Drunk driving is dangerous because, at high enough levels, alcohol impairs driving ability. As a central nervous system depressant, alcohol can impair vision, slow reactions, and decrease coordination. Vision, reaction-time, and coordination are all important to driving. Alcohol can also negatively affect a person’s ability to divide their attention among simultaneous tasks, and driving is a divided attention skill. In addition, alcohol can impair judgment and lower inhibitions, which may lead to an increased willingness to take risks.
How We Test for Drunk Driving
As driving under the influence of alcohol (or other drugs) is dangerous, the government needs methods to determine if drivers are operating under the influence. At the roadside, law enforcement officers administer standardized field sobriety tests developed by the National Highway Traffic Safety Administration (NHTSA). According to NHTSA, those tests reliably predict whether a driver has a blood alcohol concentration of .08 or higher. After a driver is arrested, the driver’s alcohol (or drug) level is determined by testing a sample of the driver’s blood, breath, or urine.
Our Testing Is A Proxy for Intoxication
Field sobriety testing and alcohol/drug testing in blood/breath/urine are circumstantial evidence that a driver operated a vehicle under the influence. Field sobriety tests do not measure driving ability: they predict blood alcohol concentration. Blood/breath/urine tests measure alcohol and drug levels, both those levels do not necessarily indicate the driver’s ability to operate the vehicle was impaired.
We’ll Go With What We Have
A more effective way of testing a suspect’s driving ability may be to have them operate a vehicle and evaluate their driving skills, like the Chikushino Police Department program. Doing so would obviously be impractical and dangerous. So, for now, we will continue to test for impaired driving with field sobriety tests and blood/breath/urine tests.