While DUI and DUI are popular acronyms for drinking and/or taking drugs and driving, the state of Massachusetts refers to this criminal act as OUI or Operating Under the Influence. If you or someone you know has recently been arrested for OUI in Massachusetts, you'll want to understand the laws to better prepare yourself for the pending penalties.

In the state of Massachusetts, a person can be charged with OUI if they provide a chemical test to police and their blood alcohol content (BAC) is found to be .08% or higher. With a BAC at or above this amount, a person can be arrested for OUI under a “per se” violation. When broken down, this violation means that a person does not have to be intoxicated or high to be charged with OUI – simply, their BAC is over the legal limit. In court, the prosecution will not have to provide any other proof of operating under the influence if they can prove your BAC was .08%. They must however prove that the reading was accurate and reliable and that is where they often fail.

Another Massachusetts OUI Law you'll want to understand is the Implied Consent Law. Every holder of a Massachusetts driver's license has already consented to providing a breath sample, or if brought to a hospital in custody, a blood sample, to be tested for alcohol and/or drugs if they are suspected of OUI. While police cannot physically force you into submitting to testing, you'll want to know that there are harsh consequences for refusal as your driver's license will automatically be suspended for six months to lifetime.

As mentioned earlier, the legal limit is .08%, but there are enhanced penalties for drivers who are found to be much higher than this amount. Any driver with a BAC of .20% or more may face harsher penalties in court.

Massachusetts has also enacted a Zero Tolerance Law for any driver under the legal drinking age of 21. Anyone under this age driving a vehicle cannot have a BAC of .02% or they will face administrative penalties with the Registry of Motor Vehicles. For OUI purposes, the level is still .08%.