REAL ADVOCACY WHEN YOU NEED IT TALK WITH US

Woman blowing into breathalyzer attached to IID in her car

How Does an Ignition Interlock Device Work?

DUI charges can carry serious consequences, often affecting a person's driving privileges, finances, and reputation. At Guilfoil Law Group, we understand the challenges individuals in Kansas City and throughout Missouri face when dealing with DUI defense.

One tool frequently discussed in these cases is the ignition interlock device. This device significantly enables individuals to maintain limited driving privileges while adhering to Missouri’s DUI laws. Understanding its functionality can help those working through DUI cases approach the situation with greater clarity.

An Overview of the Ignition Interlock Device

The ignition interlock device (IID) is a compact breathalyzer installed directly into a vehicle. Its primary function is to prevent the vehicle from starting if the driver has consumed alcohol.

Connected to the ignition system, the IID requires the driver to provide a breath sample before the engine can start. These devices are often mandated by courts as part of DUI penalties and are essential for reinstating restricted driving privileges.

The IID’s functionality hinges on several integral components:

Mouthpiece: The section where the driver blows to provide a breath sample.
Control unit: Analyzes the sample to detect alcohol levels.
Relay mechanism: Interacts with the vehicle’s ignition system to prevent operation if alcohol is detected.
Memory storage: Logs data, including breath test results and tampering attempts, for reporting to the appropriate authorities.

How an Ignition Interlock Device Operates

The operation of an IID is straightforward but involves multiple steps to verify compliance:

Starting the Vehicle

Before the vehicle starts, the driver must provide a breath sample by blowing into the IID. The device measures the blood alcohol concentration (BAC) and determines if it falls below the preset threshold, typically 0.02%. If the sample meets the requirement, the vehicle will start.

Rolling Retests

To prevent circumvention, the IID requires random breath tests while the vehicle is in motion, known as rolling retests. These tests are designed to confirm continued sobriety throughout the trip. Failing or ignoring a retest can result in alerts such as honking or flashing lights until the vehicle is stopped.

Data Reporting

All test results, including successful and failed attempts, are logged in the device’s memory. This information is transmitted periodically to monitoring agencies, such as the court, probation officers, or the Department of Motor Vehicles (DMV). This factors accountability and provides evidence of compliance.

When Is an Ignition Interlock Device Required?

Missouri law mandates IID installation in several DUI-related situations:

First offense with high BAC: Individuals convicted of a first DUI offense with a significantly elevated BAC may be required to install an IID.
Multiple DUI offenses: Repeat offenders face mandatory IID installation to regain driving privileges.
Refusal to submit to testing: Drivers who refuse breathalyzer or chemical testing during a DUI stop often face IID requirements as part of their penalties.
Restricted driving privileges: Those seeking limited driving privileges during license suspension must typically install an IID.

The IID must remain in place for the period specified by the court or DMV. To qualify for removal, individuals must:

Complete the required duration: Maintain compliance for the mandated timeframe.
Submit compliance records: Provide logs demonstrating adherence to testing and lack of tampering.

Benefits of Using an Ignition Interlock Device

While an IID may seem like a burden, it provides several advantages, particularly for individuals working to regain control of their driving privileges after a DUI charge. These benefits include maintaining mobility, demonstrating responsibility, and reducing the risk of repeat offenses:

Maintaining mobility: Allows individuals to travel to work, school, or medical appointments, minimizing disruptions to daily life.
Demonstrating responsibility: Using an IID shows a commitment to safe driving and adherence to legal requirements.
Reducing repeat offenses: Studies reveal that IIDs significantly decrease the likelihood of repeat DUI offenses, making roads safer for everyone.

Challenges Associated With Ignition Interlock Devices

Despite their benefits, IIDs come with challenges that users should be prepared to address. These challenges include cost considerations, device malfunctions, and the inconvenience of required tests:

Cost Considerations

The financial burden of installing and maintaining an IID can be significant. Installation fees typically range from $70 to $150, while monthly monitoring and calibration fees add an additional $60 to $80. These costs can accumulate over time.

Device Malfunctions

Environmental factors such as extreme temperatures can sometimes affect the device’s performance, leading to false positives or other operational issues. Regular maintenance and proper care can help mitigate these problems.

Inconvenience

The requirement to perform rolling retests while driving can disrupt travel and create additional stress for users. Proper planning and understanding of the device’s functionality can help alleviate these frustrations.

To minimize complications, consider these tips:

Clean the mouthpiece: Regular cleaning reduces the risk of inaccurate readings.
Follow calibration schedules: Timely calibration makes sure that the device operates correctly.
Plan ahead: Allocate extra time for rolling retests, especially during longer trips.

Legal Consequences of Tampering With an IID

Tampering with or attempting to bypass an IID is a serious offense under Missouri law. Consequences may include extending the required IID period, fines, or even jail time. For individuals on probation, tampering can lead to revocation and additional legal repercussions:

Extended IID requirements: Additional time may be added to the mandatory installation period.
Increased penalties: Courts can impose fines, extended license suspensions, or even jail time for tampering violations.
Probation violations: For individuals on probation, tampering with an IID can lead to revocation and other legal repercussions.

Managing Common Triggers and Maintenance

Beyond the essential operation and legal implications, individuals required to use an ignition interlock device (IID) can benefit from understanding a few additional considerations.

First, it is important to be aware of the device’s sensitivity to various substances. Certain everyday products—such as mouthwash, breath fresheners, or even some medications—may contain trace amounts of alcohol, potentially triggering a positive reading. To avoid false positives, users should carefully read labels.

Another key point is the importance of regular maintenance and servicing. Most IID providers require users to schedule monthly or bi-monthly appointments for calibration to keep the device accurate. Missing these appointments can result in the device shutting down or issuing a violation report to the monitoring agency.

Communication, Mindset, and Compliance

Maintaining open communication with your monitoring agency is essential. If a device registers a failed breath test and you believe it is in error, it is wise to contact your IID provider and probation officer (if applicable) immediately to explain the situation. Prompt reporting of any irregularities can help mitigate misunderstandings and potential penalties.

For many people, the frequent reminders to test—especially during rolling retests—can feel intrusive. However, viewing the IID as a step toward regaining full driving privileges can shift perspective in a positive way. It is a temporary measure aimed at promoting safe driving habits and compliance with Missouri’s DUI regulations.

How DUI Defense Lawyers Assist in Ignition Interlock Cases

At Guilfoil Law Group, we understand that facing DUI charges is challenging. Our firm assists clients in addressing IID requirements and other legal aspects of their cases. Our DUI defense lawyer can play a critical role in evaluating circumstances, addressing violations, and advocating for alternative solutions:

Evaluate the circumstances: Determine whether IID installation is appropriate or contest unwarranted requirements.
Address violations: Help challenge allegations of failed tests or tampering due to technical errors or medical conditions.
Advocate for alternatives: Present options for alternative penalties or negotiate reduced IID durations when applicable.

Contact Guilfoil Law Group Today

If you’re dealing with DUI charges or ignition interlock requirements in Missouri, Guilfoil Law Group is here to help. We serve clients in Kansas City and throughout Missouri, providing experienced legal guidance tailored to your needs.