An OUI arrest usually creates two different problems at once: a criminal case in court and, depending on the circumstances, a driver’s-license consequence administered under Massachusetts law. The early decisions matter because evidence can include observations, video, roadside assessments, breath-test materials, medical information, dispatch records, and statements made before and after arrest.
Arraignment is the beginning, not the trial
At arraignment, the charge is formally addressed, a plea is entered, and the court determines release conditions. The case then ordinarily proceeds through discovery and pretrial events. Counsel should use that period to identify which parts of the Commonwealth’s evidence are admissible, which are scientifically or factually contestable, and which require additional discovery.
OUI cases are built from observations
Commonwealth evidence may include driving behavior, an accident or near accident, odor of alcohol, speech, eyes, balance, admissions, conduct during booking, and performance on roadside exercises. None of those observations exists in isolation. The defense should ask what the officer actually observed, under what conditions, whether video confirms the report, and whether innocent explanations are supported by the record.
Roadside tests are evidence, not magic
Massachusetts permits officers in alcohol OUI cases to describe their observations during field sobriety exercises. But the defense can test how the exercises were instructed, where they were performed, lighting and weather, footwear, physical limitations, language comprehension, and whether the video matches the officer’s characterization.
Where no roadside tests were given, Massachusetts model instructions recognize that the absence of expected investigative steps may itself be something a jury can consider in appropriate circumstances, including whether the omitted procedure would normally be expected and whether there is an adequate explanation for the omission.
Breath-test evidence has foundational requirements
Breath evidence is governed by statute, regulation, and evidentiary requirements. The analysis can include the operator’s certification, the instrument and methodology, observation periods, proper administration, and whether the Commonwealth can establish the necessary foundation for the specific evidence it seeks to introduce.
An inadequate breath sample is not automatically the same thing as a refusal. Massachusetts appellate decisions have required the Commonwealth to establish an appropriate foundation before evidence of a failure to provide a sufficient sample can be admitted for particular purposes.
Refusal evidence raises separate issues
Massachusetts generally provides substantial protection against the use of a defendant’s refusal to provide physical evidence where no warrant or court order exists, subject to recognized exceptions such as when the defense opens the door by affirmatively presenting a misleading picture of cooperation. The precise evidentiary issue should therefore be addressed before trial rather than assumed.
Officer opinions have limits
An officer who observed a defendant may ordinarily describe observations and, within limits, offer lay opinions about sobriety. But Massachusetts law restricts opinions that simply tell the jury the legal conclusion it must reach. The distinction between describing observable impairment and opining directly on the ultimate issue can be important in motions in limine and at trial.
Video should be compared to the written report
Body-camera and booking video can be unusually important in OUI cases because jurors can often see the defendant walk, speak, follow directions, interact with officers, and understand questions. Counsel should compare the recording with every material characterization in the police report.
OUI defense is cumulative
OUI trials often turn not on one dramatic fact but on the combined strength or weakness of many observations. A defense investigation should therefore examine the entire sequence: the basis for the stop, operation, roadside interaction, arrest decision, statements, testing, booking, and any medical or accident evidence. The question is what the admissible evidence proves beyond a reasonable doubt—not what one isolated observation might suggest.
Sources and authorities
- Massachusetts law about drunk or drugged driving
- Massachusetts Guide to Evidence § 701 — opinion testimony
- Massachusetts Guide to Evidence § 511 — refusal and inadequate breath samples
About Kris Aleksov
Kris Aleksov is a Massachusetts trial and litigation attorney. He graduated from UMass Law in 2013, where he served first as an associate member and later as Executive Business Editor of the UMass Law Review. He was admitted to the Massachusetts Bar in November 2013 and is also admitted to the United States District Court for the District of Massachusetts and the United States Court of Appeals for the First Circuit.