What is the legal Blood Alcohol Concentration (BAC) limit for drivers over 21 in Massachusetts?

In Massachusetts, the legal Blood Alcohol Concentration (BAC) limit for drivers over 21 years old is 0.08%. This means that if a driver's BAC is measured at 0.08% or higher, they are considered to be operating a vehicle under the influence of alcohol, which is illegal.

The reason for this specific limit is based on extensive research that shows that at a BAC of 0.08%, a person's ability to operate a vehicle safely is significantly impaired. This impairment can include decreased coordination, reduced reaction times, and compromised judgment, all of which increase the risk of accidents on the road.

In contrast, lower BAC limits or thresholds indicated in other options would not reflect current legal standards for adult drivers in Massachusetts and would not adequately capture the impairment associated with higher alcohol consumption levels. Thus, a BAC of 0.08% is recognized as the point at which the state determines that a driver poses a danger to themselves and others while driving.