Driver's License Test Prep
The Glossary · A–Z

Zero tolerance law

Also known as: zero-tolerance law, under-21 alcohol law

A law that holds drivers under age 21 to a blood-alcohol-concentration limit at or near zero, far below the limit that applies to adults. A reading at or above the under-21 threshold is itself grounds for license suspension, whether or not the driver shows any sign of impairment. The threshold and the penalties attached to it are set by state law.

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