How Many Interlock Violations Can You Have in Massachusetts?

In Massachusetts, the number of ignition interlock violations you can have before the RMV takes action depends on which rule you broke. Four types of conduct count as a violation on the first occurrence, one type counts after a single failed rolling retest at 0.05 BAC or higher, and four other types require two incidents before the RMV treats them as a formal violation.¹ Any confirmed violation can lead to a license revocation of up to ten years, and in some cases a lifetime loss.

Violations That Count on the First Incident

Four categories of IID violations give you no second chance. One occurrence is enough for the RMV to act:¹

Operating any vehicle that does not have your required interlock device installed.
Having another person blow into the device for you, whether at startup or during a rolling retest.
Providing a sample by any means other than blowing directly from your own mouth.
Tampering with the device in any way, including attempts to disable, alter, or bypass it.

A fifth situation also triggers a violation on a single occurrence: one failed rolling retest with a breath alcohol concentration at or above 0.05, at any point during your entire IID obligation period.¹ The device itself is calibrated to a 0.02 BAC limit, so a small amount of alcohol will keep the vehicle from starting, but it is the 0.05 reading on a rolling retest that produces a stand-alone violation.²

Violations That Require Two Incidents

Four other categories require two occurrences before the RMV counts them as a violation:¹

Two failed rolling retests with a BAC between 0.02 and 0.05, both within the same service period.
Two lockouts caused by missed rolling retests, counted across your entire IID obligation.
Two missed service visits, counted across your entire obligation.
Two lockouts caused by failed startup tests, counted across your entire obligation.

The counting rule matters more than the number two. For missed rolling retests, missed service visits, and startup-test lockouts, the RMV adds them up across your entire IID obligation, which for repeat OUI offenders can run several years. A lockout in month three and another in month fourteen combine into one violation. You do not get a fresh count at each service visit.

Only the 0.02 to 0.05 rolling retest category uses a shorter window. Both failures must happen within the same service period, and service visits run roughly every 25 to 30 days. A 0.03 reading in January and a 0.04 reading in March fall in different service periods and would not combine.

Startup tests work in two stages. After one failed attempt, the device enters a holding period. If the second attempt also reads above 0.02, the IID goes into lockout mode and you have 48 hours to bring the vehicle to your service provider for a data download and reset.³

What a Lockout Does Before Any Hearing

A lockout is not the same as a violation, but it is the mechanism that reports most violations to the RMV. When the device locks out, you have 48 hours to get to an approved vendor. The vendor uploads the data, resets the device, and sends the incident to the RMV. Miss the 48-hour window and the device enters permanent lockout. The vehicle will not start, and you have to tow it to the service center at your own expense.³

The same thing happens if you miss a service visit by more than 30 days past your last calibration. Immediate lockout, and the tow is on you. The indigency program does not cover these towing costs.

What the RMV Does After a Confirmed Violation

If a hearings officer finds you responsible for an IID violation, the license consequences are serious. Revocation can last up to 10 years, and repeat offenders or those with especially serious violations can lose their license for life.¹ The RMV also has authority to take immediate action to protect public safety, which means your driving privileges can be suspended before the hearing takes place.

Your IID period can also be extended. If your original interlock restriction was for less than six months and the hearings officer finds violations during that time, the restriction is extended an additional six months from the date of the most recent violation.¹ For hardship license holders, a confirmed violation means losing that license and becoming ineligible for another one for at least 10 years.

Extensions also stack when it comes time to remove the device. The IID does not come off on a calendar date. You have to apply and appear before a hearings officer, who reviews your entire compliance record. If violations show up in that record, the restriction gets extended rather than lifted.¹

The Criminal Charge for Driving Without the Device

One violation category carries a criminal penalty on top of anything the RMV does. Driving a vehicle that does not have your required IID installed is punishable by a fine of $1,000 to $15,000 and a mandatory minimum jail sentence of 150 days. The maximum is two and a half years in a house of correction, or two and a half to five years in state prison. The 150-day minimum cannot be reduced, suspended, or avoided through probation or parole.²

This is the trap that catches people off guard. Borrowing a friend’s car, taking a rental, or driving the wrong family vehicle all expose you to a mandatory jail sentence that no judge can waive.

Contesting a Lockout or Violation

When a lockout is reported, the RMV schedules a hearing. If you believe the lockout was not justified, you have 30 days from the lockout to request a hearing and contest it. Miss the 30-day window and the lockout stands. You cannot challenge it later.¹

At the hearing, you can present evidence explaining the circumstances. Common explanations include a BAC reading caused by mouthwash or a medical condition, a missed rolling retest caused by a device malfunction, or a missed service visit tied to a documented emergency. The hearings officer reviews the data downloaded from the device and decides whether the violation is justified. Skipping the hearing is worse than losing it. If you do not appear, the RMV can revoke your license indefinitely.

Appealing to the Board of Appeal

If the RMV hearings officer upholds the violation, you can appeal to the Board of Appeal on Motor Vehicle Liability Policies and Bonds. The appeal requires a written request and a non-refundable $50 fee paid by check or money order. Hearings are conducted virtually by video or telephone.⁴

One boundary to keep in mind: the Board only reviews decisions made by the Registrar. If your license was revoked by a court rather than the RMV, the appeal goes through the court system instead.⁴

1
Mass.gov. Ignition Interlock Device Program
2
General Court of Massachusetts. Massachusetts General Laws Part I, Title XIV, Chapter 90, Section 24S
3
Massachusetts Registry of Motor Vehicles. Ignition Interlock Device Overview
4
Mass.gov. Appeal a Decision of the Registrar of Motor Vehicles