OUI in Massachusetts: the law, the limits and the device
Verified · next review
Massachusetts calls it OUI — operating under the influence, and you will see DUI and drunk driving used for the same offense. What follows is what this state sets, taken from its own published rules rather than from a national summary.
What Massachusetts law actually requires
Massachusetts marks the license itself — "HT" for a hardship license with interlock, "T" for interlock alone — expressly so that officers can identify these drivers at a stop. The program came out of Melanie’s Law in 2005 and is run by the Driver Control Unit of the RMV.
- First offense: For the whole hardship license period; multiple-OUI offenders keep the device a further two years after full reinstatement. Since 1 July 2021 certain first offenders seeking a hardship license need one too
- Lockout threshold: Set by the certification rules at 540 CMR 25.00, under which the RMV certifies the providers that install and monitor the device
- Program run by: Massachusetts RMV, Driver Control Unit
Source: www.mass.gov, checked 2026-08-23
DUI vs OUI in Massachusetts
Massachusetts uses OUI, and the difference from plain DUI is worth getting right: both describe driving impaired, and locally the charge is written as OUI — operating under the influence
Whatever it is called, the licensing consequence is the same shape: a suspension, then the device as the condition of driving again. All six abbreviations, side by side →
Can you get a OUI on a bike or a horse in Massachusetts?
It turns on one word in the statute. Where the law says “vehicle”, no engine is required and the charge can reach a bicycle, a horse or a mobility scooter. Where it says “motor vehicle”, the analysis is different. This is decided by your state’s own wording, not by national custom, and it is the first thing to check before assuming a bike ride home is safe.
Where this state departs from the national picture
Most of what people read about drunk driving is written for the country as a whole. These are the points where Massachusetts does something of its own.
Immediate, with no notice period
Refusing is not a crime in Massachusetts — it is an administrative suspension that starts at once, with no notification period. Even an acquittal does not reverse it automatically: you have to file a motion asking the court to reinstate.
How often this happens in Massachusetts
Federal crash records show the scale the state is legislating against, and how it compares with the country.
Cases are heard where the stop happened, and volume shapes local practice. These MA counties record the most:
Source: NHTSA Fatality Analysis Reporting System, 2020–2022. Counts crashes where police recorded that a driver had been drinking, which is narrower than the federal 0.08 measure and therefore understates the real figure. Massachusetts runs above the national share.
What it costs to get driving again in Massachusetts
Massachusetts does not publish a price cap we could verify, so the quote is the number and your only leverage is a competitor nearby. The national reference points are installation and a monthly fee, with calibration visits every 30 to 60 days.
Massachusetts costs, providers and all 106 cities with centers →
The two clocks in Massachusetts
The court case and the licensing case run separately. The licensing side moves first, and in the strictest states the window to request a hearing is measured in days — it runs whether or not you have hired anyone.
Massachusetts cities
The county that hears your case is set by where the stop happened, and local practice differs across the state.
OUI questions in Massachusetts
Is it called DUI or OUI in Massachusetts?
Massachusetts uses OUI — operating under the influence. You will also see DUI, drunk driving used for the same thing. The label follows the state, not the seriousness of what happened, so paperwork from elsewhere may say something different about identical conduct.
What is the legal limit in Massachusetts?
0.08% for drivers 21 and over, as in every state except Utah, which sits at 0.05%. Below the limit you can still be charged if an officer documents impairment. The reading that triggers the interlock here is a separate number: Set by the certification rules at 540 CMR 25.00, under which the RMV certifies the providers that install and monitor the device
How long does the interlock stay on after a first offense in Massachusetts?
For the whole hardship license period; multiple-OUI offenders keep the device a further two years after full reinstatement. Since 1 July 2021 certain first offenders seeking a hardship license need one too The program is run by Massachusetts RMV, Driver Control Unit.
Can you get an OUI on a horse or a bicycle in Massachusetts?
The answer is in whether the statute says “vehicle” or “motor vehicle”. Where it says vehicle, no engine is needed and the charge can reach a bike or a horse; where it says motor vehicle, it cannot. This is one of the most searched questions in the whole subject and one of the most confidently answered wrongly — the wording of your own state decides it.
When an OUI is a felony in Massachusetts →A first OUI here →A second OUI here →
When a charge becomes a felony → The test and the refusal → SR-22 and FR-44 →
Attorney advertising. InterlockDeviceNearMe is not a law firm, does not practice law, and does not give legal advice. Nothing here creates an attorney-client relationship. Requesting a consultation connects you with an independent attorney or a legal referral service, who decide separately whether to take your case. Case outcomes depend on facts we do not know, and no result is ever promised. Deadlines in DUI cases are short and vary by state — speak to a licensed attorney in your state before relying on anything you read here.