A Massachusetts State Police trooper is facing an operating-under-the-influence charge after Boston officers say they found him slumped over in the driver’s seat of a BMW early Saturday near Herald and Washington streets. The driver, identified in court as Trooper Donovan Preston, allegedly showed signs of impairment and refused a breath test. He was arraigned this week in Boston Municipal Court, where a not-guilty plea was entered on his behalf. His attorney declined to comment and, as of March 25, 2026, State Police had not publicly confirmed his duty status, as per WCVB.
Trooper allegedly found slumped behind the wheel
Boston police say the encounter unfolded shortly after 5 a.m. Saturday near Herald and Washington streets, where they reported finding 31-year-old Preston in the driver’s seat of a BMW with his eyes closed and the vehicle still in drive, according to WCVB. The police report cited by the station states an open High Noon hard seltzer was sitting in the cupholder and that officers noted slurred speech and glossy eyes. Preston allegedly stumbled as he got out of the car.
What refusing a breath test actually triggers
Refusing a breath test might seem like a way to avoid evidence in an OUI case, but in Massachusetts it comes with its own automatic fallout. Under the state’s implied-consent rules, declining a chemical test brings administrative penalties that are separate from anything that happens in criminal court. As outlined by Mass.gov, a first-time refusal typically leads to an immediate 180-day suspension by the Registry of Motor Vehicles, vehicle impoundment and a short window of 15 days to request an RMV hearing.
OUI case moves into Boston Municipal Court
Preston appeared in Boston Municipal Court on Monday, where he was formally charged with OUI and a not-guilty plea was entered on his behalf, according to WCVB. His attorney, Benjamin Megrian, declined to comment as prosecutors move forward with the case.
Another headache for State Police leadership
Preston’s arrest lands at a tense moment for Massachusetts State Police, which has been dealing with a run of personnel and integrity issues in recent years. The Boston Globe reported last October that a newly sworn trooper resigned following an off-duty OUI arrest. Separate from alcohol cases, federal prosecutors have pursued corruption-related charges against former troopers, according to the U.S. Department of Justice.
The criminal case against Preston remains pending in Boston Municipal Court. Any administrative fallout tied to his alleged refusal of a breath test will be handled separately by the RMV. This story will be updated as new court filings and official statements emerge.
