Massachusetts OUI Laws: Penalties, BAC & License (2026)

In Massachusetts the offense is called operating under the influence (OUI), and General Laws Chapter 90, Section 24 makes it unlawful to operate a motor vehicle with a blood alcohol concentration (BAC) of 0.08 percent or more. A first OUI is punishable by a fine of $500 to $5,000 and up to two and one-half years in a house of correction, plus a license loss.

This guide is part of our DUI Laws by State series.

What counts as an OUI in Massachusetts

Massachusetts charges the offense as operating under the influence under General Laws Chapter 90, Section 24. The statute can be proven two ways: by showing a BAC of 0.08 percent or more (the per se theory), or by showing that liquor or another substance actually impaired the driver's ability to operate safely (the impairment theory). Because the impairment theory does not require a specific number, a driver can be convicted below 0.08 if the Commonwealth proves diminished capacity. Commercial drivers face a 0.04 percent limit, and drivers under 21 fall under a zero-tolerance rule that bars a BAC of 0.02 percent or more, triggering an immediate license suspension. The 0.08 figure is the federal benchmark adopted by every state except Utah, which uses 0.05 percent, as the National Highway Traffic Safety Administration describes. Massachusetts uses "OUI" where other states say DUI or DWI, but the conduct is the same.

First-offense OUI penalties in Massachusetts (jail, fines, suspension)

Under Chapter 90, Section 24, a first OUI is punishable by a fine of not less than $500 nor more than $5,000 and imprisonment for up to two and one-half years. In practice, most first offenders resolve the case through the 24D disposition, a statutory alternative that places the person on probation for up to two years, requires a 16-week Driver Alcohol Education program, and substitutes a shorter license suspension for jail. As the Massachusetts RMV explains, a 24D first offender typically faces a license suspension of 45 to 90 days and is eligible to apply for a hardship (work or education) license. A straight conviction without 24D carries a one-year license loss. Fees, assessments, and program costs add substantially to the fine.

Watch out: A breath-test refusal suspension runs separately from the criminal case and from any court-ordered suspension. You serve the refusal suspension even if the OUI charge is later reduced or dismissed, and you generally have only a short window to appeal it to the RMV.

Ignition interlock requirements in Massachusetts

Massachusetts does not require an ignition interlock device for every first OUI. Under Melanie's Law, codified in Chapter 90, Section 24 1/2, the interlock requirement applies to drivers with two or more OUI convictions or program assignments, who must install the device before any new or reinstated license and keep it for at least two years. As the Massachusetts RMV describes, the device is also required as a condition of any hardship license issued to a repeat offender. A standard first-time offender resolving the case through the 24D program generally does not need an interlock, although that can change if a hardship license is sought after a refusal suspension. The device requires a clean breath sample before the engine starts and at random points while driving.

License suspension and the administrative (RMV) process in Massachusetts

Massachusetts runs two license tracks at once. The administrative track is the RMV's immediate action based on the breath test or refusal, separate from the criminal court case. As the Massachusetts RMV explains, a driver 21 or older who registers 0.08 percent or more faces a 30-day suspension, while a driver who refuses the test faces a 180-day suspension on a first offense. The criminal court then imposes its own outcome: a 24D disposition carries a 45-to-90-day suspension with hardship eligibility, while a straight conviction carries a one-year loss. The arresting officer takes the license, and the driver may appeal a refusal suspension to the RMV within a short statutory window. Reinstatement requires paying fees, completing any program, and, for repeat offenders, installing an interlock.

Repeat offenses and the Massachusetts look-back period

Massachusetts is among the strictest states on prior offenses because it uses a lifetime look-back period. Under Chapter 90, Section 24, every prior OUI conviction or assignment to an alcohol program counts toward enhancement no matter how many years have passed, in Massachusetts or in another state. A second OUI carries a longer suspension and mandatory interlock on reinstatement, and the felony threshold sits at the third offense: a third OUI is a felony punishable by mandatory jail time, a fine up to $15,000, and an eight-year license loss. A fourth OUI carries a 10-year license loss, and a fifth is punishable by up to five years in state prison with a lifetime license revocation. Operating to cause serious injury or death is charged as a felony regardless of offense number.

Watch out: Refusing the breath test does not protect your license and can hurt more than failing it. A first refusal triggers a 180-day suspension, and the refusal suspension climbs to three years for a driver with one prior OUI and to five years or life for drivers with multiple priors.

Refusing a breath or blood test in Massachusetts

Massachusetts is an implied consent state, meaning that by driving you are deemed to have agreed to a chemical test if arrested for OUI. According to the Massachusetts RMV, a first refusal results in a 180-day license suspension, a refusal by a driver with one prior OUI results in a three-year suspension, two priors bring a five-year suspension, and three or more priors bring a lifetime suspension. These refusal suspensions are administrative and are served on top of any court penalty. Because the refusal penalty for a first offender (180 days) is longer than the 30-day breath-test-failure suspension, and because a refusal can still lead to conviction on the impairment theory, refusing rarely helps the license outcome. The driver may appeal the refusal suspension to the RMV.

Can you expunge or seal an OUI in Massachusetts

Massachusetts does not allow expungement (the destruction of a record) for an OUI conviction, and OUI is specifically excluded from the state's adult expungement statute. The available remedy is sealing, which limits public access to the record without destroying it. A misdemeanor OUI conviction or a continuance without a finding (CWOF) can generally be sealed three years after the case ends, and a felony OUI (a third or later offense) can generally be sealed after seven years, provided the person stays out of trouble in the meantime. A sealed OUI still counts as a prior under the lifetime look-back rule, so it does not reset the offense count for any future case. Cases that ended in a not-guilty finding or dismissal may be sealable sooner.

What to do after an OUI arrest in Massachusetts

A Massachusetts OUI creates two matters at once: a criminal case in the District Court and an administrative license case at the RMV. The deadlines are short, so a common first step is to act quickly on any breath-test refusal suspension, because the appeal window to the RMV is brief and the suspension takes effect immediately. The criminal case proceeds separately, and many first offenders weigh whether the 24D disposition fits their situation. General information cannot tell you how your case will come out, since the outcome depends on the specific facts, the evidence, and your record. Many people consult a licensed Massachusetts OUI attorney to understand the charge, the RMV deadlines, and the trade-offs between 24D and trial. Keep the citation, the suspension notice, and any test results in a safe place.