The statute: It is a crime to operate a motor vehicle on a public way while under the influence of intoxicating liquor, marijuana, narcotic drugs, depressants or stimulants, or the vapors of glue.
What the Commonwealth must prove:
- The defendant operated a motor vehicle.
- The defendant did so on a public way, or in a place where the public has a right of access, or in a place where members of the public have access as invitees or licensees.
- At the time of operation, the defendant was under the influence of intoxicating liquor (or another substance covered by the statute) — meaning the alcohol or substance had diminished the defendant’s ability to operate the vehicle safely. The Commonwealth does not have to prove the defendant was drunk, only that his or her ability to drive safely was reduced.
Penalties: For a first offense: up to 2½ years in the house of correction and a fine of $500–$5,000. Most first offenders are eligible for the alternative disposition under § 24D — probation, completion of an alcohol education program, and a license loss of 45–90 days rather than the standard one-year revocation. Penalties escalate sharply for repeat offenses: a second offense carries a mandatory minimum jail term, and a third offense is a felony with a mandatory minimum of 150 days. Collateral consequence: loss of your driver’s license, plus higher insurance costs and a criminal record that can affect employment.
In plain English: You do not have to be falling-down drunk, and you do not have to blow a particular number, to be charged. If the police believe alcohol or drugs made you a less safe driver, that is enough to charge you — but the Commonwealth still has to prove it beyond a reasonable doubt.
How these cases are defended:
- Challenging the traffic stop itself — if the stop was unlawful, the evidence that followed may be suppressed.
- Attacking the field sobriety tests: how they were explained, administered, and scored, and whether road, weather, footwear, or medical conditions affected performance.
- Challenging breath test results — machine calibration, the 15-minute observation period, operator certification, and compliance with testing regulations.
- Raising “operation” and timing issues, including whether the Commonwealth can prove the defendant was impaired at the time of driving rather than afterward.
- Negotiating a § 24D disposition or a continuance without a finding where the facts allow.
This page is general information about Massachusetts law, not legal advice about any specific case. If you are charged with a crime, contact Davis Law Firm, P.C., 132 Lincoln Street, Suite 5L, Boston, MA 02111, (617) 297-4837.
