Massachusetts DUI Laws in 2026

Massachusetts DUI laws cover drivers who operate motor vehicles while impaired by alcohol, cannabis, opioids, and other mind-altering substances.

What Constitutes a DUI in Massachusetts?

Before we explore Massachusetts DUI laws, we need to clarify the terminology that we’ll be using in today’s post. The three most common terms for driving while impaired by alcohol or another drug are:

• DUI – Driving under the influence
• DWI – Driving while intoxicated
• OUI – Operating under the influence 

Massachusetts law uses the term operating under the influence (OUI) when referring to this behavior. However, since DUI and DWI are frequently used by other state governments, and are commonly employed in casual conversations, we’ll be using all three terms interchangeably throughout the rest of the post. 

Having established that, let’s turn our attention back to the question of how Massachusetts defines operating under the influence.

Massachusetts law

Massachusetts DUI laws are spelled out in Massachusetts General Laws, Chapter 90, Section 24. According to the opening paragraph of this section, it is illegal to operate a motor vehicle if you:

• Have a blood alcohol content (BAC) of 0.08% or higher.
• Are under the influence of “intoxicating liquor, or of marijuana, narcotic drugs, depressants or stimulant substances.”
• Are under the influence from “smelling or inhaling the fumes of any substance having the property of releasing toxic vapors.”

Blood alcohol content 

Having a BAC of 0.08% or higher is the commonly recognized standard for getting a DUI anywhere in the U.S. That’s because a federal law signed in 2000 mandated that all states meet the 0.08% standard by 2004 or lose a percentage of federal highway construction funds.

However, as the second and third bullet points in the previous section indicate, a driver in Massachusetts can be charged with a crime if they are under the influence of any mind-altering substance, including both legal and illicit drugs.

Also, the 0.08% BAC limit only applies to drivers age 21 and above who are operating a private vehicle. 

For any driver under 21, it is illegal to drive with any alcohol in their system at all. So, for example, a 19-year-old with a BAC of 0.02% can be arrested and charged with an OUI in Massachusetts.

For those with a commercial driver’s license (CDL), the OUI threshold is 0.04%.

Other substances

The amount of other drugs in a person’s system can’t always be measured as easily or precisely as blood alcohol content can. So Massachusetts DUI laws don’t include BAC-like standards for cannabis (marijuana), opioids, or other substances. 

Instead, determinations of OUIs for drivers who have been using other drugs depend on observations such as:

• Smell of marijuana on a person’s clothing
• Slurred or otherwise abnormal speech 
• Bloodshot eyes
• Dilated or constricted pupils
• Involuntary eye movements (nystagmus)
• Poor balance and/or coordination
• Memory problems

Drivers who are detained for suspicion of DUI in Massachusetts may also be asked to submit blood or urine to be tested for the presence of certain drugs. It is legal to refuse to take these tests, but that denial can be used against a person as their case progresses through the legal system.

What Are the Penalties for Violating Massachusetts DUI Laws?

The penalty for violating Massachusetts DUI laws can vary depending on several factors, including your age, if you have previously received a DUI, and who was in the car with you at the time:

• A first DUI may be punished with a fine of $500-$5000, license suspension for up to one year, and jail time up to 2.5 years. However, Chapter 90, Section 24D of the Massachusetts General Laws allows for probation and a reduced suspension if the individual meets certain criteria.
• A second DUI may result in a fine of up to $10,000, license suspension of up to two years, jail time up to 2.5 years, and the required installation of an ignition interlock device on the individual’s car. Some second OUI offenders may also be eligible for the Section 24D diversion program linked to in the previous bullet point. Second offenders may also be eligible for a 14-day inpatient intervention.
• First-time offenders who had children under the age of 14 in the car while driving under the influence face a fine of $1,000-$5,000 and a minimum jail sentence of 90 days. Multiple offenders with children under the age of 14 in the car may be fined up to $10,000 and jailed for a minimum of six months. The mandatory minimum jail sentences may be suspended for first offenders, but not for those with multiple offenses.
• In addition to facing fines, license suspension, and jail time, drivers under 21 who receive a DUI must also participate in the Youth Alcohol Program (YAP)

Is a DUI a Sign of Addiction?

The terms DUI, OUI, and DWI don’t appear in the addiction criteria in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). But driving while under the influence fits into the eighth criteria below:

1. Having powerful cravings for the substance
2. Frequently using the substance in greater amounts or for a longer period than intended
3. Having a persistent desire to stop using the substance, but being unable to do so
4. Spending a considerable amount of time on activities related to acquiring, using, and recovering from the effects of the substance
5. Continuing to use the substance after incurring physical or psychological harm that was caused or worsened by prior use
6. Continuing to use the substance after having social or interpersonal problems that were caused or worsened by prior use
7. Failing to meet responsibilities at home, in school, or at work as a result of your substance use
8. Using the substance in circumstances that pose a clear physical hazard
9. Reducing or ending your participation in important social or work-related activities because of your substance use
10. Developing tolerance, or needing to use larger amounts of the substance to experience its effects
11. Having withdrawal symptoms when you abruptly curtail your substance use

To be diagnosed with a mild substance use disorder (addiction) as established in the DSM-5, you only have meet two of the criteria above. Having four or five of these symptoms is classified as a moderate substance use disorder, while exhibiting six or more qualifies as a several substance use disorder.

If you suspect that you have become addicted to alcohol or another drug, a good first step would be to consult with your doctor or schedule an assessment at a reputable addiction treatment provider near you. Receiving an accurate diagnosis can help you understand the scope of the challenge you’re facing so you can find the most appropriate treatment.

Learn More About Treatment for Alcohol Addiction in Massachusetts

Lake Avenue Behavioral Health provides personalized outpatient care for adults whose lives have been disrupted by addictions and co-occurring mental health concerns. We offer a high intensity outpatient program (similar to a day treatment or partial hospitalization program) and an intensive outpatient program (IOP) with both day and evening options.

To learn more about how we can help you or a loved one, or to schedule a free assessment, please visit our Admissions page or call us today.