Massachusetts OUI/DUI FAQs

OUI stands for Operating Under the Influence — Massachusetts's term for what other states call DUI or DWI. Under M.G.L. c. 90, § 24, a person commits OUI by operating a motor vehicle on a public way while under the influence of alcohol or a controlled substance, or with a blood alcohol concentration (BAC) of .08 or above. The .08 BAC threshold creates a per se violation — it does not require proof of impaired driving, only proof of the reading. For drivers under 21, the Junior Operator Law (M.G.L. c. 90, § 24P) applies a zero-tolerance standard — a .02 percent BAC triggers enhanced penalties. For CDL (commercial driver's license) holders, the federal threshold is .04.

A first OUI conviction under M.G.L. c. 90, § 24 is a misdemeanor punishable by up to 2.5 years in a House of Correction and a fine of $500 to $5,000. Most first-time offenders are eligible for the 24D alternative disposition program — named after M.G.L. c. 90, § 24D — which involves a probationary period, a 45-to-90-day license loss, and completion of an alcohol education program, in lieu of a committed sentence. The 24D program is available once in a lifetime, with the exception of Cahill dispositions discussed here. License suspension under the 24D disposition is imposed by the court as a criminal penalty and is separate from the RMV administrative suspension triggered at the time of arrest.

A second OUI conviction under M.G.L. c. 90, § 24 carries a mandatory minimum of 60 days in a House of Correction (with 30 days to serve), a two-year license revocation, and a fine of $600 to $10,000. A third OUI is a felony carrying a mandatory minimum of 180 days in a House of Correction (with 150 days to serve), an eight-year license revocation, and a fine of $1,000 to $15,000. A fourth or subsequent OUI is a felony with mandatory state prison exposure of up to five years and permanent license revocation. Prior OUI convictions from other states count toward Massachusetts's prior offense calculation.

Yes. Under Massachusetts law, a person is "operating" a motor vehicle even when it is not in motion, provided the ignition is engaged. The SJC has held that operation requires only that the defendant had control of the vehicle and engaged the ignition — actual movement is not required. A person asleep in a running car in a parking lot can be charged with OUI under M.G.L. c. 90, § 24. Defense of a parked-car OUI focuses on the specific facts of the ignition state and the defendant's intent at the time of contact by police.

This is one of the most consequential decisions in an OUI arrest. Under Massachusetts's implied consent law (M.G.L. c. 90, § 24(1)(f)(1)), declining the breathalyzer triggers an automatic RMV license suspension — 180 days for a first offense, three years for a second, five years for a third. However, refusing the test eliminates the prosecution's primary scientific evidence of BAC. Without a breathalyzer result, the Commonwealth must prove OUI through officer testimony about driving behavior, field sobriety tests, and general observations — a harder evidentiary burden to meet. Whether to take or refuse the test depends on specific circumstances and should be evaluated with counsel immediately after arrest. See: Why a Failed Breathalyzer Does Not Equal an OUI Conviction.

Before accepting any plea, it is worth knowing the alternatives. The dispositions that avoid a conviction, and the grounds for an outright dismissal, are mapped on dismissals, not guilty verdicts, and the alternatives to a guilty plea.

This is one of the most consequential decisions in an OUI arrest. Under Massachusetts's implied consent law (M.G.L. c. 90, § 24(1)(f)(1)), declining the breathalyzer triggers an automatic RMV license suspension — 180 days for a first offense, three years for a second, five years for a third. However, refusing the test eliminates the prosecution's primary scientific evidence of BAC. Without a breathalyzer result, the Commonwealth must prove OUI through officer testimony about driving behavior, field sobriety tests, and general observations — a harder evidentiary burden to meet. Whether to take or refuse the test depends on specific circumstances and should be evaluated with counsel immediately after arrest. See: Why a Failed Breathalyzer Does Not Equal an OUI Conviction.

No. The result of a portable breath test (PBT) administered on the roadside is strictly inadmissible at trial in Massachusetts as evidence of BAC. Roadside PBT devices are considered insufficiently reliable for evidentiary purposes. An officer may use the PBT result to establish probable cause for an arrest, but the number produced by the roadside device cannot be shown to a jury. Only the result of the station-house Draeger Alcotest 9510, administered under the strict protocols of 501 CMR 2.00, is admissible at trial — and even that result is subject to multiple challenges. See: Massachusetts OUI Breathalyzer Defense.

Yes — and effectively. The Draeger Alcotest 9510 is the only breathalyzer approved for evidentiary use in Massachusetts under 501 CMR 2.00. Its results are subject to challenge on multiple grounds. First, the 15-minute continuous observation period required before administration — if the officer broke visual contact at any point, a Motion to Suppress is available. Second, the calibration and maintenance records of the specific machine used must be reviewed — the Commonwealth v. Ananias litigation resulted in the exclusion of over 27,000 breath tests statewide after the Office of Alcohol Testing withheld failed calibration records from defense counsel. Third, if the two required breath samples vary by more than .02%, the result is invalid under 501 CMR 2.00. Fourth, the result can be contextualized at trial against video evidence, field sobriety performance, and witness testimony showing sobriety. See: Why a Failed Breathalyzer Does Not Equal an OUI Conviction.

No. Field sobriety tests — the Horizontal Gaze Nystagmus (HGN), Walk and Turn (WAT), and One Leg Stand (OLS) tests developed by the National Highway Traffic Safety Administration (NHTSA) — are voluntary in Massachusetts. A driver may refuse them without triggering an automatic license suspension. However, an officer can and will use refusal of field sobriety tests as supporting evidence of probable cause for an OUI arrest, and the refusal can be mentioned at trial. The decision to perform or decline field sobriety tests has strategic implications that depend on the specific circumstances of the stop.

Not automatically. The right to remain silent under Miranda protects against self-incriminating statements made during a custodial interrogation. If an officer failed to issue Miranda warnings before questioning you in custody, statements made during that interrogation — "I had three beers," "I came from a party" — can be suppressed through a Motion to Suppress. However, the suppression of statements does not automatically dismiss the underlying charge. The physical evidence of OUI — the breathalyzer result, the officer's driving observations, the field sobriety test performance — remains unaffected by a Miranda violation. Suppression of key statements can, however, significantly weaken the prosecution's case.

Not without additional justification. Under the Fourth Amendment and Article 14 of the Massachusetts Declaration of Rights, a traffic stop for suspected OUI does not automatically authorize a search of the vehicle. Police need independent probable cause or a recognized exception — consent, plain view, or search incident to a lawful arrest — to search a car during an OUI stop. A warrantless vehicle search unsupported by one of these exceptions is unconstitutional, and evidence obtained from it — drugs, open containers, weapons — can be suppressed through a Motion to Suppress.

An OUI arrest in Massachusetts triggers an immediate administrative license suspension by the RMV under the implied consent law — independent of any court proceedings. If you refused the breathalyzer: 180-day suspension (first offense), three years (second), five years (third).
A fourth OUI is a felony carrying a 10-year license revocation, and a fifth or subsequent OUI is a felony carrying a lifetime license revocation, each with state prison exposure and a mandatory minimum term of incarceration.
If you took the breathalyzer and registered .08 or above: 30-day suspension (first offense), 30 days (second), 30 days (third). These administrative suspensions take effect at the police station and are not dependent on a conviction. Winning the criminal case does not automatically restore the RMV administrative suspension — a separate proceeding at the RMV or a court order is required. See: Massachusetts OUI License Suspensions.

A hardship license, sometimes called a Cinderella license, permits limited driving during a single 12-hour period each day, seven days a week, for documented work, education, or medical needs. It is discretionary, not automatic. The applicant must demonstrate a genuine hardship and the absence of reasonable alternative transportation, and a first application is made to an RMV hearings officer. A denial can be appealed to the Board of Appeal on Motor Vehicle Liability Policies and Bonds, a separate body within the Division of Insurance.
For a first offense resolved through a 24D disposition, a hardship license may be sought shortly after the disposition is entered and the person has enrolled in the Driver Alcohol Education program. Under amendments to Melanie's Law effective July 1, 2021, a first offender who obtains a hardship license must install an ignition interlock device (IID) for the duration of the hardship period, at the driver's expense.
For a driver with one or more prior OUI offenses, M.G.L. c. 90, § 24½ requires an IID for any hardship license and for full reinstatement, and it must remain installed for two years after reinstatement. The hard suspension period before hardship eligibility and the treatment-program requirements increase with each offense, and third and fourth offense hardship requests must be approved by the Director of the RMV Driver Control Unit.
A chemical test refusal carries a separate administrative suspension, 180 days for a first offense and longer with priors, that runs consecutively to any court suspension and cannot be waived by the Board of Appeal. During a second or subsequent refusal suspension, no hardship license is available. On a first offense, hardship relief generally becomes available only once the underlying OUI case has been resolved, which is why the timing of the disposition matters when a refusal suspension is also in place.

A CWOF on an OUI charge avoids a formal guilty conviction under Massachusetts law but carries significant consequences. It still requires an admission to sufficient facts. It triggers a license suspension — identical to a guilty conviction suspension under 24D for a first offense. For CDL holders, FINRA-regulated financial professionals, healthcare licensees, and most federal employees, a CWOF is treated identically to a conviction and can trigger license revocation or job loss. For immigration purposes, a CWOF is a conviction under federal law regardless of Massachusetts's classification. A CWOF on an OUI charge also counts as a "prior offense" for purposes of calculating penalties on any future OUI charge — permanently eliminating the benefit of the first-offense disposition. It should never be accepted without a full assessment of its collateral consequences.

Massachusetts OUI law (M.G.L. c. 90, § 24) applies to impairment by any controlled substance, not just alcohol. OUI-Drugs charges arise when police believe a driver is impaired by marijuana, prescription medications, heroin, cocaine, or any other substance. There is no BAC-equivalent threshold for drugs — the Commonwealth must prove impairment through officer observations, field sobriety tests, and the testimony of a Drug Recognition Expert (DRE). There is no approved breathalyzer for cannabis or other drugs in Massachusetts. Blood or urine tests may be obtained with a warrant if the driver is involved in an accident causing serious injury. Defense of OUI-Drugs cases focuses on the subjective reliability of DRE methodology and the officer's qualifications.

OUI causing serious bodily injury under M.G.L. c. 90, § 24L is a felony carrying a mandatory minimum of six months, up to two and one-half years in a house of correction or up to ten years in state prison, and a two-year license revocation. OUI causing death is most often charged as motor vehicle homicide while operating under the influence under M.G.L. c. 90, § 24G(a), a felony punishable by two and one-half to fifteen years in state prison, or one to two and one-half years in a house of correction, with a one-year mandatory minimum and a 15-year license revocation. The most serious charge, motor vehicle manslaughter under M.G.L. c. 265, § 13½, carries up to twenty years in state prison and a five-year mandatory minimum when the operation involved OUI.

The decision is yours, made with the benefit of full legal advice after reviewing all available evidence. Not every OUI case goes to trial — cases with strong evidence of BAC and impaired driving are frequently resolved through negotiation for the best available plea. Cases with constitutional vulnerabilities — an illegal stop, a defective warrant, a flawed breathalyzer — are strong candidates for a Motion to Suppress that can eliminate key evidence and result in dismissal. Cases with a questionable stop, borderline BAC, and video showing good balance and coherent speech are strong trial candidates. Attorney Serpa has a perfect record of not-guilty verdicts in OUI jury trials in Massachusetts District Court and the BMC. Every case is prepared for trial from the first day of representation.

Yes. An OUI conviction in Massachusetts is a lifetime entry on the RMV driving record and is used to calculate the "prior offense" count for any future OUI charge regardless of how many years have passed. Unlike most other states, Massachusetts has no look-back period for OUI priors — a conviction from 30 years ago counts as a prior offense. Sealing the CORI entry for an OUI conviction under M.G.L. c. 276, § 100A does not affect the RMV driving record — the RMV and the CORI are separate systems. The RMV driving record remains accessible to insurance companies and the RMV regardless of a CORI seal.