Brief States Identify Effective Ignition Interlock Countermeasures to Fight DUIs

One person dies every 45 minutes in a drunk driving crash in the United States. Recent data also shows that 11,654 people were killed in alcohol-impaired traffic crashes in 2020, a 14.3% increase from 2019. Alcohol-impaired driving fatalities made up 30% of all 2020 traffic fatalities.

Polysubstance-impaired driving—driving after using a mix of drugs or a combination of drugs and alcohol--also contributes to the increasing number of impaired driving crashes. Recently collected data from trauma centers revealed that 20% of injured or killed roadway users tested positive for two or more categories of drugs, including alcohol.

States recognize that impaired driving is a major traffic safety and public health issue and have adopted a variety of measures to combat this dangerous behavior. These efforts include establishing harsh sanctions for driving under the influence (DUI). However, the effectiveness of these laws is uncertain and highly dependent upon enforcement and adjudication efforts.

One proven intervention, laws requiring the use of ignition interlock devices (IIDs) by first-time or repeat DUI offenders until there is proven compliance for an extended time period, have proven to reduce or prevent impaired driving when certain best practices are followed.

IIDs are connected to the starter or other on-board computer system in a motor vehicle to prevent the car from being operated if a set level of alcohol, usually .02, is detected on the driver’s breath. Most devices require random retesting while the car is running to ensure that the driver is not drinking once the car is started. Studies show that IIDs reduce recidivism—by up to 70%— among first-time, repeat and high-risk offenders while they are installed.

The nation’s traffic safety community has a favorable perception of IIDs and generally agrees they are one of the most powerful tools in the fight against alcohol-impaired driving. In a study of rural Arizona judges’ perception of IIDs, one judge noted that “it is the safest way of trying to get someone to comply with not drinking and driving, especially people that habitually have problems.”

Given their noted benefits, IIDs have become a popular impaired driving intervention considered by state legislatures. State interlock laws vary in several ways as some states require the use of IIDs pretrial while others only mandate their use once the offender is convicted. Most states require IIDs for all offenders whereas other states only require interlocks for repeat and/or high BAC offenders. Similarly, IID program durations can vary from six months to 10 years or a lifelong requirement for offenders with multiple convictions.

While all states have passed IID laws, the focus has shifted to addressing gaps in state interlock laws and enforcement efforts that can be a major obstacle to their effectiveness and use, as there is still a relatively low installation rate among eligible offenders, according to the Traffic Injury Research Foundation. To address some of these challenges, states have amended their laws through interventions such as:   

• Requiring all offenders to install an IID.
• Granting an immediate provisionary driver’s license upon installation of an IID.
• Removing the ability to wait out the IID period.
• Requiring IID installation upon chemical test refusal.
• Enacting compliance-based removal provisions.

State Action

All Offender IID Installation

Most traffic safety experts advocate for requiring all offenders—also known as universal interlock requirements—to install an IID. An article studying the effects of ignition interlock laws on fatal crashes between 1982 and 2013 found that mandatory laws for all offenders “would have significant public health benefit” and “are more effective at reducing alcohol-involved fatal crashes than laws requiring interlocks for segments of high-risk offenders.” A more recent study concluded that states with universal interlock laws saw an average 15% decrease in alcohol-involved crash deaths compared with states with less stringent interlock requirements.

Currently, 30 states and the District of Columbia require all offenders to install an IID. Other states only require IIDs for repeat and/or high BAC offenders. New Mexico became the first state to require IID for all convicted drunk drivers in 2005.

• Kentucky (SB 85, 2019) and New Jersey (SB 824, 2019) were the most recent states to require all DUI offenders to install an IID.

Immediate Provisionary Driver’s License Upon IID Installation

Offenders must often wait months before obtaining a restricted license that allows them to drive safely with an interlock. As a result, some states allow individuals to install an IID as soon as possible after a drunk driving offense to ensure they can continue driving to essential locations like work, while also protecting public safety. 

• Arizona (SB 1334, 2022) recently removed the 90-day driver’s license suspension period for certain DUI offenders who refused a chemical test to determine impairment. Offenders must apply for a special IID restricted license after completing any ordered alcohol or drug screening.
• Colorado (SB 55, 2022) passed legislation to permit an individual whose license has been revoked for one year or more because of a conviction like a DUI, or for nine months for a first offense, to immediately apply for an ignition interlock-restricted license. Previously, offenders had to wait until their license was revoked for one month before applying for reinstatement.
• North Carolina (HB 402/SB 183, 2021) eliminated the six-week waiting period for certain offenders to install an IID, allowing for limited driving privileges immediately following their final conviction. Offenders with limited driving privileges and an IID are permitted to drive at all hours of the day and install IIDs only in the vehicles they drive.

No Ability to Wait Out the IID Period

Another intervention states use to increase interlock installations is to require DUI offenders to provide proof of successful use of an IID before obtaining unrestricted driving privileges. These efforts can address loopholes within laws that allow DUI offenders to wait out their license suspension period without practicing sober driving with an IID.

• Arkansas (A.C.A. § 5-65-118) and Kansas (K.S.A. 8-1015) require proof of installation of an IID, which is often submitted by the device provider to a designated state agency, for the entire license suspension period before an offender’s unrestricted driving privileges are reinstated.
• Delaware (HB 152, 2020) recently amended its interlock law to require all offenders whose driving privileges have been revoked to install IID in their vehicles if they want to drive during the license revocation period. Previously, DUI offenders could avoid having to install an IID if they obtained a limited license that allowed them to drive to certain places, such as their workplace.

IID upon Chemical Test Refusal

All driver’s license applicants agree to comply with requests by law enforcement officers to take breath or blood samples to determine impairment when they sign their driver’s license application forms. These laws, called implied consent laws, are based on the premise that driving is a privilege and not a right. Every state has some sort of implied consent law, and the penalties for offenders who refuse to submit a test often include mandatory or incentivized IID installation, which can involve reducing driver license suspension periods, among other incentives. An average of 24% of suspected drunk drivers nationwide refuse to submit to a chemical test upon arrest, according to the latest data available.

• In Colorado (C.R.S. § 42-2-132.5), if an individual refuses to submit a chemical test they are subject to an automatic two-year IID installation as a condition of license reinstatement after they have served two months of the revocation period.   
• Idaho (HB 551, 2018) recently required individuals who refuse chemical testing to install an IID for one year. If an offender commits two refusals within 10 years, they must install an IID for two years.
• Virginia (HB 34, 2020) allowed first time offenders convicted of violating its implied consent law to request a restricted driver’s license. The court may grant the petition if it finds good reasons to do so, but the offender must install an IID on each motor vehicle they own and successfully complete an alcohol safety action program.

IID Compliance-Based Removals

To combat attempts to drive drunk or circumvent or tamper with an IID, several states have enacted laws that require offenders to install an IID for a certain period without violations before removal is possible. Experts agree that effective compliance-based removal laws clearly define what constitutes a violation and require all violations to be reported.

• Washington (RCW 46.20.720) monitors IID program participants through a Compliance Based Review period of 180 days. To be eligible for removal, offenders may not fail a test within that 180-day timeframe—defined as attempting to start their vehicle with a BAC of .04 or more, .020 for a retest—fail to take a random retest, attempt to circumvent or fail to appear when required for maintenance, repair, calibration, monitoring, inspection or replacement of the device.
• Maryland (Md. Code, Transp. § 16-404.1) requires an offender to go 90 days before a participant’s date of release from the IID program with no reported fails on the interlock before the device can be removed. A randomized trial in Maryland showed that components of the state’s close monitoring program, including reviewing reporting data received, and sending letters to offenders informing them of violations and their consequences, reduced failed tests and tampering attempts.
• Tennessee enacted legislation (HB 2184/SB 2434, 2022) that restarts the interlock usage period for IID restricted driver’s license holders if they remove, tamper or circumvent their device or fail to comply with maintenance and inspection requirements.

In addition to preventing offenders from removing the device until the mandated period has expired, tampering with or circumventing IIDs triggers other penalties in most states—usually a term of imprisonment and/or a fine.

Cameras are increasingly also used to prevent tampering with an interlock and ensure it is the driver who is blowing and not someone else. Currently, 21 states require IIDs to be equipped with a camera.

Federal Action

IID laws fall under the jurisdiction of individual states. However, federal laws contain incentive grant provisions for states if they pass IID laws that meet certain criteria. To receive an Ignition Interlock Law Grant (23 U.S.C. 405 (d)), states must meet several requirements, including enacting and enforcing “mandatory alcohol-ignition interlock law(s) for all individuals convicted of driving under the influence of alcohol or of driving while intoxicated.” The federal Infrastructure Investment and Jobs Act, enacted in November 2021, preserved the previous grant criteria, but also expanded eligibility to include states that prohibit a convicted DUI offender from driving unless they install an IID on all vehicles they own for at least 180 days. States also qualify for assistance if they require any convicted offender or license revokee who has refused a chemical test to possess an interlock for at least 180 days without any violations for the last 40% of the installment period.  

Did You Know?

• 80% of drivers surveyed in 2019 supported IID requirements for all DUI offenders.
• Ignition Interlocks have stopped 29 million attempts to drive after alcohol consumption over the last decade.
• The monthly cost estimate, which includes monitoring, maintenance and lease fees, for an IID falls between $70 to $125, or $2-4 a day. Installation and removal can cost between $100 and $250. Many states have established affordability programs to ensure that people who are struggling financially will be able to install IIDs.