September 21, 2026
Infractions

What Is an Ignition Interlock Device in Connecticut and Who Needs One?

If you have been arrested or convicted for DUI in Connecticut, you have almost certainly heard the term ignition interlock device — or IID. It comes up at the bail hearing, in the sentencing discussion, in the DMV administrative process, and as a condition of license restoration. An IID may become part of a DUI case at different stages, including during the court process and as a condition of license restoration.

Despite how frequently the IID comes up in DUI proceedings, many people — including those facing the requirement — do not fully understand what it is, exactly how it works, who is required to have one, for how long, and what happens if they do not comply. This article answers all of those questions clearly and honestly.

If you are facing a DUI charge or an IID requirement in Connecticut, call Flannery Law for legal guidance.

What Is an Ignition Interlock Device?

An ignition interlock device is a breath-testing instrument that is physically installed in a motor vehicle. Under Connecticut General Statutes § 14-227j, the IID measures the blood alcohol content of the driver before allowing the engine to start. The device measures the operator’s blood alcohol content and prevents the vehicle from starting until the operator’s blood alcohol content is less than 0.025%.

In practical terms, the IID works like this: before starting the vehicle, the driver must blow into a handheld mouthpiece connected to the device. The device analyzes the breath sample. If the BAC reading is below 0.025%, the vehicle starts normally. If the reading exceeds 0.025%, the vehicle will not start and the failed attempt is logged.

Most modern IID devices also require periodic rolling retests — the driver must provide a breath sample while the vehicle is already in motion, the device may require additional breath samples while the vehicle is being operated. This prevents a driver from passing the initial test and then consuming alcohol while driving. If a rolling retest is failed or not completed, the device logs the failure and typically triggers a warning signal.

IID providers monitor compliance with the IID program and report violations as required by Connecticut law and regulations.

Who Is Required to Have an Ignition Interlock Device in Connecticut?

The IID requirement arises at multiple points in the Connecticut DUI process — not just at conviction. Understanding when and why the requirement applies is important for anyone navigating a DUI case.

As a Condition of Bail or Release After Arrest

Under Connecticut General Statutes § 14-227j(b), a court may order a person who has been arrested for DUI — even before any conviction — not to operate any motor vehicle unless it is equipped with an IID. This order can be imposed as a condition of bail, as a condition of probation, or as a condition of participation in a pretrial program.

Because a court may impose an IID order before a conviction, the requirement may begin before the criminal case is resolved. For many people, this is the first practical encounter with the device.

As a Condition of License Restoration After Administrative Suspension

Following the DMV administrative suspension that occurs after a DUI arrest under Connecticut General Statutes § 14-227b, the driver must install an IID on every vehicle they own or operate as a condition of license restoration. The length of the IID requirement following administrative suspension depends on the history:

For drivers who submitted to testing and registered an elevated BAC:

First suspension: six months IID
Second suspension: one year IID
Third or subsequent suspension: two years IID

For drivers who refused chemical testing:

First refusal: one year IID
Second refusal: two years IID
Third or subsequent refusal: three years IID

The IID requirement following a refusal is longer than the administrative IID requirement following an elevated test result for drivers age 21 and older.

As a Mandatory Condition of Conviction

Upon conviction for DUI under Connecticut General Statutes § 14-227a, the IID is a mandatory condition of license restoration at every offense level. The required IID periods following conviction are:

First conviction: 45-day license suspension followed by a one-year IID requirement following restoration.

Second conviction within ten years: 45-day license suspension followed by a three-year IID requirement. During the first year of the three-year period, driving is limited to work, school, an alcohol or drug treatment program, an IID service center, or an appointment with a probation officer.

Third or subsequent conviction: A third or subsequent conviction results in permanent license revocation. A person may request a hearing for reconsideration after at least two years, subject to the statutory requirements

For DUI with a Child Passenger

A conviction under Connecticut General Statutes § 14-227m, carries specific license suspension and IID requirements that depend on whether it is a first, second, or third/subsequent offense. One year for a first offense, three years with first-year travel restrictions for a second offense, and permanent revocation for a third offense.

For School Bus and Children’s Vehicle DUI

Under Connecticut General Statutes § 14-227n, operating a school bus or vehicle designated for children while under the influence carries a three-year IID requirement following the mandatory license suspension, with first-year restricted operation for violations involving child passengers.

For Felony DUI — Assault and Manslaughter

Under Connecticut General Statutes § 53a-60d (assault in the second degree with a motor vehicle) and § 53a-56b (manslaughter in the second degree with a motor vehicle), convictions under these statutes carry specific license-suspension and IID consequences that depend on the offense and applicable statutory provisions.

The IID Applies to Every Vehicle You Own or Operate

This is one of the most important — and most frequently misunderstood — aspects of the Connecticut IID requirement. The requirement is not limited to one designated vehicle. Under § 14-227j, the order applies to every motor vehicle owned or operated by the person subject to the requirement.

This means if you have two cars at home, both must have IIDs installed. A person subject to an IID requirement generally may not operate a vehicle unless the vehicle is equipped with the required approved IID, subject to any applicable statutory exception. Driving any vehicle without an IID during the restriction period is a violation and can result in additional consequences— even if that vehicle belongs to someone else and the driver only operated it briefly.

This creates practical complications for people whose jobs require them to operate employer vehicles, or whose household members share vehicles. These situations need to be discussed with an attorney and potentially addressed with the DMV.

Who Pays for the Ignition Interlock Device?

All costs associated with the installation and maintenance of an ignition interlock device are borne entirely by the driver. Under § 14-227j(c), the person subject to the IID order pays for installation, monthly calibration and maintenance fees, and any removal fees at the end of the restriction period.

Installation typically costs between $70 and $150. Monthly monitoring fees generally range from $60 to $100. Over a one-year restriction period, the total cost can easily reach $800 to $1,200 or more. For longer restriction periods — two or three years — the cumulative cost is substantial.

Courts are not permitted to waive IID fees under § 14-227a(i)(2), which specifically states that no court may waive any fees or costs associated with the installation and maintenance of an ignition interlock device.

What Devices Are Approved in Connecticut?

Not every IID on the market can be used to satisfy a Connecticut court or DMV order. Under § 14-227j(d), only devices approved under regulations adopted by the Commissioner of Motor Vehicles pursuant to § 14-227a(i) may be installed pursuant to a court order.

The Connecticut DMV maintains a list of approved IID providers. Installation must be performed by a firm approved and authorized by the Commissioner. Using an unapproved device — even one that functions correctly — does not satisfy the legal requirement and can result in the driver being treated as non-compliant.

What Happens If You Violate the IID Requirement?

Violations of IID requirements are treated seriously and have real consequences. Under § 14-227a(i)(3), regulations adopted by the Commissioner of Motor Vehicles specify what constitutes a failure to comply with IID requirements and the consequences that follow.

Common violations include:

Failed start tests: A BAC reading above 0.025% that prevents the vehicle from starting may be logged and reported
Failed rolling retests: Failing to complete a rolling retest or failing the retest with an elevated reading
Missed calibration appointments: Failing to bring the device in for required maintenance and calibration
Tampering or circumventing the device: Any attempt to bypass, disable, or have another person blow into the device
Operating a non-IID-equipped vehicle: Driving any vehicle without a compliant IID installed

The consequences of violations can include extension of the IID restriction period, reinstatement of a license suspension, additional charges, or revocation of any conditional license.

Under § 14-227j(e), if a person subject to an IID court order holds a special operator’s permit issued under § 14-37a, strict compliance with the IID order is a condition of that permit — and any failure to comply is sufficient cause for immediate revocation of the permit by the Commissioner.

Can the IID Requirement Be Challenged or Reduced?

The IID requirement following a DUI conviction is mandatory — it is not discretionary and cannot be waived by the court. However, there are legitimate circumstances in which the IID period can be affected:

Winning the DMV hearing: If the administrative suspension is not affirmed — because the hearing officer finds in the driver’s favor on one of the four statutory issues — the IID requirement triggered by the administrative process does not apply. The criminal conviction IID requirement, if any, would still apply separately.

Dismissal of charges: If the DUI charge is dismissed — through a successful defense, a not-guilty verdict, or a future pretrial program — no conviction-based IID requirement applies. This is one of the strongest arguments for fighting a DUI charge vigorously rather than accepting a quick plea.

Successful defense of the criminal charge: A not-guilty verdict eliminates the conviction-based IID requirement entirely.

What cannot be reduced is the mandatory IID period following a conviction. The applicable IID period is determined by the governing statute and the driver’s circumstances.

The IID and Under-21 Drivers

For drivers under 21, the IID framework applies with the same force as for adult drivers. Connecticut General Statutes § 14-227g subjects under-21 drivers to the zero-tolerance BAC threshold of 0.02%, and the administrative and conviction-based IID requirements follow the same framework as standard DUI cases.

Young drivers subject to an IID requirement face practical challenges around cost, vehicle access, and the logistics of compliance while managing school, work, and family obligations. Early legal representation that seeks to avoid the conviction in the first place is the most effective protection against a long-term IID requirement.

Frequently Asked Questions

Does the IID requirement apply even before I am convicted? Yes. Under § 14-227j(b), a court can order an IID as a condition of bail or release immediately after arrest — before any conviction. The IID requirement can also arise from the DMV administrative suspension process, which runs parallel to the criminal case.

What happens if I drive a vehicle without an IID during the restriction period? Driving a vehicle without a required IID is a violation of the court order and can result in extension of the restriction period, reinstatement of your suspension, and potentially additional criminal charges. It is treated very seriously.

Can someone else blow into the IID for me? No — and attempting to have someone else provide the breath sample is a form of tampering that constitutes a serious violation. IID devices are designed to detect attempts at circumvention, and many have cameras that record the person providing the breath sample.

What if my employer requires me to drive a company vehicle without an IID? This is a situation that needs to be addressed carefully with your attorney and potentially with the DMV. There are limited provisions for employer vehicle exceptions in some circumstances, but they are narrow and require formal documentation.

Will the IID affect my insurance? The IID requirement itself is not typically reported directly to insurance companies, but the underlying DUI conviction — which triggered the IID — is reflected on your driving record and will affect insurance premiums.

What happens when the IID restriction period ends? At the end of the restriction period, you must have the device removed by an authorized provider, obtain documentation of successful completion of the program, and notify the DMV. Only after formal confirmation from the DMV that the restriction has ended can you operate a vehicle without the device.

Can a DUI conviction and its IID requirement ever be erased? Under Connecticut General Statutes § 54-142a(e), a DUI conviction may be eligible for record erasure ten years after the most recent conviction date — provided all sentence conditions are completed and no new DUI conviction occurs during that period. However, the DMV driving record is separate from the criminal record, and § 54-142a(e)(6) specifically states that the DMV is not required to erase criminal history record information from a driving record.

Contact Flannery Law for the right legal counsel.

Courts Where Flannery Law Handles DUI Cases in Connecticut

From our offices in Hartford, Westport, and Farmington, we represent clients facing DUI charges and IID-related issues across Connecticut. Our team appears regularly in the following courts:

Connecticut Superior Courts

Charging practices and plea negotiations may vary by courthouse.

Understanding the IID Is Part of Understanding the Full Cost of a DUI

The ignition interlock device is not just a technical requirement — it is a daily reminder of the consequences of a DUI conviction, and a financial burden that extends for months or years beyond the end of any suspension period. For many people, the cumulative cost of the IID over a one, two, or three-year period exceeds every other financial consequence of the case.

Understanding the full scope of what a DUI conviction means — including the IID requirement — is one of the strongest reasons to fight the charge from the very beginning rather than accepting an outcome without understanding what it entails.

At Flannery Law, we make sure every client understands exactly what they are facing before making any decision about their case — we help clients understand the potential consequences of a DUI charge and evaluate their available legal options.

Legal Disclaimer: The information and articles on this website are provided for general informational purposes only and are not legal advice. Viewing this website does not create an attorney-client relationship. Laws and legal developments may change, and some content may not reflect the most recent updates. Case outcomes depend on the specific facts, prior record where applicable, relevant statutes, and court rulings.