For most drivers, New Jersey has a blood alcohol content limit of .08 percent, which translates to .08 grams of alcohol per 100 milliliters of blood in a person’s system. A driver who has a BAC of .08 percent or more is automatically considered driving under the influence.
However, for drivers under the age of 21, New Jersey has adopted a zero-tolerance policy toward intoxication. Any driver under 21 who has any detectable alcohol in their system can be charged with DUI. Commercial drivers over the age of 21 are subject to a lower BAC limit of .04 percent while they are operating a commercial vehicle.
Even if a driver has a BAC below the New Jersey DUI limit, they can still be charged with DUI if other evidence tends to show that their intoxication has impaired their ability to safely operate a vehicle.