Crossing the Massachusetts–New Hampshire border may take only a few minutes, but the laws that apply after an impaired-driving arrest can change significantly depending on which side of that border you are on.

Massachusetts generally uses the term OUI, or Operating Under the Influence. New Hampshire generally uses DWI, or Driving While Intoxicated. Although both states prohibit driving while impaired by alcohol or drugs, the difference is more than terminology.

The two states have different rules concerning license suspensions, chemical tests, test refusals, first-offense penalties, treatment requirements, aggravated offenses, and administrative hearings. Those differences can become particularly important for people who live in one state but are arrested in the other.

Here is a closer look at Massachusetts OUI versus New Hampshire DWI and what drivers should understand about the process.

Massachusetts OUI vs. New Hampshire DWI at a Glance

Issue	Massachusetts OUI	New Hampshire DWI
Common term	OUI – Operating Under the Influence	DWI – Driving While Intoxicated
BAC limit for most drivers 21+	.08%	.08%
BAC threshold for drivers under 21	.02% for license-related consequences	.02%
First failed chemical test – administrative license consequence	Generally 30 days for BAC of .08% or higher for drivers 21+	Generally 6 months for a first administrative suspension with no qualifying prior
First chemical-test refusal with no qualifying prior	180-day suspension	180-day suspension
Refusal evidence in criminal case	Generally not admissible against the defendant in a criminal or civil proceeding	May be admissible
Standard first-offense license consequence after conviction	Generally 1 year, although qualifying first offenders may receive a 45–90 day suspension through a §24D disposition	9 months to 2 years, with the possibility of suspending part of the revocation when statutory requirements are met
Separate aggravated DWI offense	Not structured the same way as NH	Yes, including BAC of .16% or higher and certain aggravating circumstances

Massachusetts prohibits operating a motor vehicle with a BAC of .08% or greater or while under the influence of alcohol, marijuana, certain drugs, or other intoxicating substances. New Hampshire similarly prohibits driving while impaired or with an alcohol concentration of .08% or greater and sets a .02% threshold for drivers under 21.

The similarities, however, begin to disappear once an arrest occurs.

The Traffic Stop and OUI/DWI Investigation

An OUI or DWI case often begins with a traffic stop. An officer may report observing speeding, weaving, a lane violation, an equipment issue, or another reason for initiating the stop. Some cases begin after an accident, at a checkpoint, or when police encounter a vehicle that is already stopped.

After making contact with a driver, the officer may look for signs the officer believes indicate impairment, including the smell of alcohol, speech patterns, balance, coordination, driving behavior, statements made by the driver, or other observations.

The investigation may then include field sobriety exercises and, depending on the circumstances, alcohol or drug testing.

That does not mean every observation made by an officer or every test result automatically establishes guilt. The circumstances surrounding the stop, the investigation, the administration of tests, and the reliability and admissibility of evidence can all become important issues in an OUI or DWI case.

Chemical Testing Is Where Massachusetts and New Hampshire Begin to Look Very Different

Both Massachusetts and New Hampshire have implied consent laws connected to chemical testing after an impaired-driving arrest. But the consequences and procedures are not identical.

Massachusetts Chemical Testing

For a Massachusetts driver age 21 or older, a breath or qualifying chemical test showing a BAC of .08% or higher generally results in a 30-day administrative license suspension. This suspension arises from the test result itself and is separate from whatever ultimately happens to the OUI charge in court.

A driver can therefore face a license consequence before the criminal OUI case has been resolved.

New Hampshire Chemical Testing

New Hampshire also has an administrative license suspension system, but the initial suspension for a failed test can be considerably longer.

When a driver submits to testing that shows an alcohol concentration of .08% or more—and there is no prior DWI conviction, prior refusal, or prior administrative license suspension—the administrative suspension is generally six months. If a qualifying prior exists, the suspension can be two years. The suspension becomes effective 30 days after notice, and New Hampshire provides a process for requesting administrative review or a hearing.

That creates a significant distinction between the states: a first failed breath test can mean a 30-day administrative suspension in Massachusetts versus six months in New Hampshire.

What Happens If You Refuse a Breath or Chemical Test?

Refusing chemical testing does not necessarily prevent license consequences, and refusal works differently in Massachusetts and New Hampshire.

Refusing a Chemical Test in Massachusetts

For a driver with no qualifying prior offense, refusing the requested chemical test after an OUI arrest generally results in a 180-day license suspension.

The suspension increases substantially when prior OUI convictions, program assignments, or prior refusals are involved. Massachusetts also generally requires refusal-related suspensions to be served separately from other OUI-related suspensions.

A driver seeking to challenge a Massachusetts chemical-test refusal suspension has a short window. The RMV states that a driver is entitled to a refusal hearing within 15 days of the suspension, and the issues considered at that hearing are limited.

Massachusetts also has an important evidentiary rule: evidence that a person refused the chemical test generally cannot be used against that person in a criminal or civil proceeding, although it can be considered in specified RMV and license proceedings.

Refusing a Chemical Test in New Hampshire

A first New Hampshire chemical-test refusal with no qualifying prior DWI or refusal generally results in a 180-day suspension. A prior DWI or prior refusal can increase that period to two years.

Unlike Massachusetts, however, New Hampshire law provides that a refusal may be admitted into evidence in a criminal or civil proceeding arising from the alleged impaired driving.

That is a major difference between the two states and one reason advice based on an OUI case in Massachusetts should not automatically be applied to a DWI investigation in New Hampshire.

Drivers facing a New Hampshire administrative suspension may request an administrative review or hearing, but the request generally must be received within 30 days of the notice.

What Happens After an OUI Arrest in Massachusetts?

The criminal case and the driver's license consequences should be considered separately.

Under Massachusetts law, a first OUI conviction can carry a fine of $500 to $5,000, up to 2½ years of incarceration, and a one-year license suspension.

However, many qualifying first offenders may be eligible for what is commonly called a 24D disposition.

Under Massachusetts General Laws Chapter 90, §24D, an eligible person may be placed on probation and assigned to a driver alcohol education program. For a driver age 21 or older, the related license suspension is generally 45 to 90 days, rather than the standard one-year first-offense suspension. Different provisions apply to drivers under 21.

Eligibility and the ultimate outcome depend on the person's history and the circumstances of the case, so the existence of the 24D program does not mean every first OUI case will end the same way.

What Happens After a DWI Arrest in New Hampshire?

New Hampshire follows a different sentencing structure.

A standard first DWI conviction under RSA 265-A:2 is a Class B misdemeanor. Current law provides for a minimum $500 fine, impaired-driver programming and screening requirements, and a driver's license revocation of at least nine months and up to two years. The court may suspend up to six months of that license revocation when statutory requirements involving screening, evaluation when required, education, and compliance are satisfied.

New Hampshire law also allows a person, under specified circumstances, to ask the court at least one year after conviction to reduce a first DWI conviction to a violation. The court may consider the person's subsequent driving record, recommendations from the impaired driver program, hardship caused by a criminal record, and other relevant factors.

That procedure is another example of why comparing only the maximum penalty in each state does not tell the entire story.

New Hampshire Has a Specific Aggravated DWI Offense

One of the most noticeable differences between Massachusetts and New Hampshire is New Hampshire's Aggravated DWI statute.

A New Hampshire DWI can become aggravated based on circumstances that include:

• An alcohol concentration of .16% or higher

• Driving more than 30 mph above the applicable limit

• Causing a collision resulting in serious bodily injury

• Attempting to elude law enforcement

• Carrying a passenger under age 16

• Certain other circumstances specified by statute

Aggravated DWI carries increased penalties, including higher minimum fines, longer license consequences, and, depending on the type of aggravated DWI, mandatory incarceration and ignition-interlock requirements.

Massachusetts does not structure an ordinary OUI case around the same .16% “Aggravated DWI” category. That does not mean aggravating circumstances are unimportant in Massachusetts; rather, the charges and potential consequences are organized differently.

License Consequences Can Exist Separately From the Criminal Case

One of the most confusing parts of either an OUI or DWI arrest is that the driver's license issue may proceed separately from the criminal charge.

A person could be defending the OUI or DWI allegation in court while simultaneously dealing with an RMV or DMV suspension arising from a failed chemical test or refusal.

That distinction matters because the deadlines, issues that can be challenged, and procedures are different.

For example, Massachusetts provides a 15-day hearing window for certain chemical-test refusal challenges. New Hampshire generally allows 30 days to request review or a hearing following notice of an administrative license suspension.

Waiting for the first criminal court date before looking at the license issue can therefore create problems.

What If You Live in Massachusetts but Get a DWI in New Hampshire?

This is common in border communities throughout the Merrimack Valley and southern New Hampshire.

If a Massachusetts resident is arrested while driving in New Hampshire, the criminal case is generally handled under New Hampshire law because the alleged offense occurred in New Hampshire.

But that does not mean Massachusetts can be ignored.

New Hampshire's administrative license statute applies to nonresident driving privileges, and when the affected driver has a license from another jurisdiction, New Hampshire provides for notice of the suspension to be sent to the licensing authority in the state that issued the driver's license.

Massachusetts may then have its own consequences based on the out-of-state matter.

The Massachusetts RMV considers a driver's entire history when determining OUI-related suspension periods and counts qualifying OUI convictions and alcohol-program assignments from other jurisdictions.

So a New Hampshire DWI does not necessarily remain a “New Hampshire problem” for a Massachusetts licensed driver.

What If You Live in New Hampshire but Get an OUI in Massachusetts?

The same general concern works in the other direction.

A New Hampshire resident arrested for OUI in Massachusetts will generally face the Massachusetts criminal case and Massachusetts consequences relating to the privilege to drive in Massachusetts.

But New Hampshire law recognizes reasonably equivalent impaired-driving convictions from other jurisdictions when determining whether an offense qualifies as a prior DWI. Prior out-of-state offenses can therefore affect the treatment of a later New Hampshire case.

This is especially important for drivers who have lived, worked, or driven regularly in both states.

Prior OUI and DWI Cases Can Follow You Across State Lines

Neither state should be viewed in isolation when a driver has an impaired-driving history.

Massachusetts looks beyond Massachusetts convictions when calculating certain OUI-related consequences. New Hampshire likewise provides for qualifying, reasonably equivalent out-of-state convictions when determining prior-offense penalties.

That means an older Massachusetts OUI may become relevant in a later New Hampshire DWI case, and a New Hampshire DWI may affect how the Massachusetts RMV treats a later Massachusetts OUI.

Exactly how a prior disposition will be treated can depend on the prior offense, the date, the type of disposition, and the law involved.

OUI and DWI Cases Depend on More Than the BAC Number

Whether the arrest occurs in Massachusetts or New Hampshire, the breath-test number is only one part of the case.

Issues that may need to be reviewed can include:

• Why the vehicle was stopped

• Whether the officer had sufficient legal grounds for the stop or arrest

• The officer's observations

• Statements allegedly made by the driver

• Field sobriety testing

• Breath-testing procedures

• Blood or other chemical testing

• Medical or physical conditions affecting observations or tests

• Video from police vehicles or body-worn cameras

• Police reports and witness accounts

• Prior OUI or DWI history

• Administrative license procedures

• Whether the evidence can legally be admitted in court

The appropriate defense depends on the facts and evidence in that particular case.

Frequently Asked Questions About Massachusetts OUI and New Hampshire DWI

Is OUI in Massachusetts the same thing as DWI in New Hampshire?

They are similar impaired-driving offenses, but they are governed by different state laws. Massachusetts commonly calls the offense OUI, while New Hampshire commonly uses DWI. The BAC limit for most adult drivers is .08% in both states, but license suspensions, testing rules, sentencing structures, administrative procedures, and other consequences can differ significantly.

Is .08% the legal limit in both states?

For most drivers age 21 and older, both Massachusetts and New Hampshire use .08% as a statutory alcohol threshold. A driver can still potentially face an impaired-driving charge based on evidence of impairment even when the case is not based on a BAC of .08% or greater.

Can Massachusetts suspend my license for a New Hampshire DWI?

Potentially. A New Hampshire arrest can affect a Massachusetts resident's privilege to drive in New Hampshire, and New Hampshire can report license actions to the driver's home licensing authority. Massachusetts also considers qualifying out-of-state OUI/DWI history when determining certain RMV consequences.

Can a Massachusetts OUI count as a prior DWI in New Hampshire?

It may. New Hampshire law allows reasonably equivalent impaired-driving convictions from another jurisdiction to be considered when determining prior DWI offenses and penalties.

Should I wait until court to deal with my license?

Not necessarily. Administrative license proceedings can have deadlines that arrive before the criminal case is resolved. Massachusetts and New Hampshire have different procedures and deadlines, so the license issue should be reviewed promptly after an arrest.

Facing an OUI in Massachusetts or DWI in New Hampshire?

Living near the Massachusetts–New Hampshire border means people routinely live in one state, work in the other, and drive between the two. An impaired-driving arrest can therefore create legal and licensing issues on both sides of the state line.

Russman & Phinney Law represents clients facing OUI charges in Massachusetts and DWI charges in New Hampshire. Our attorneys can review the traffic stop, field sobriety testing, chemical-test evidence, police reports, license consequences, prior history, and other circumstances that may affect the case.

If you were arrested for OUI in Massachusetts, DWI in New Hampshire, or are concerned about how an arrest in one state could affect your driver's license in the other, contact Russman & Phinney Law to discuss your case and your options.

603-772-3433 or 351-500-1446

Disclaimer: This article provides general information about Massachusetts and New Hampshire law and is not legal advice. OUI and DWI laws and individual circumstances vary, and legal requirements may change.