What Happens If Someone Else Blows Into Your Interlock? Serious Consequences Revealed

September 30, 2025 •

4 min read

According to the Centers for Disease Control and Prevention, alcohol-impaired driving resulted in 13,424 deaths in 2022, highlighting the seriousness of DUI offenses that often lead to ignition interlock device mandates. If you're wondering what happens if someone else blows into your interlock, the answer is a serious legal violation with severe penalties for both the vehicle owner and the person assisting.

Quick Summary

Allowing another person to blow into an ignition interlock device is a serious violation that triggers consequences like extended IID use, license suspension, fines, and potential jail time. Modern devices use advanced anti-tampering technology, including cameras and random retests, to detect and report circumvention attempts to monitoring authorities, regardless of who provided the sample.

Key Points

Serious Legal Violation: Allowing another person to blow into your interlock device is a serious offense considered an act of circumvention and will result in a violation logged and reported to authorities.
Advanced Detection Technology: Modern interlock devices are equipped with sophisticated anti-tampering measures, including rolling retests, integrated cameras, and GPS tracking, to prevent and detect any attempt to cheat the system.
Owner is Responsible: The ignition interlock device owner is legally accountable for all violations recorded by the device, even if someone else was driving or provided the breath sample.
Extended Penalties: A recorded violation can trigger a range of punishments, including an extension of the time you are required to have the interlock device, suspension or revocation of your driver's license, and additional fines and court costs.
Legal Trouble for Both Parties: Both the IID owner and the individual who assists in the circumvention can face legal consequences, with the helper potentially charged with a misdemeanor depending on state laws.
Risk of Jail Time: Repeated or severe interlock violations can escalate to more serious legal action, potentially leading to a period of jail time depending on state regulations.

An ignition interlock device (IID) is a critical tool for public safety, mandated for drivers with a history of alcohol-related driving offenses. Its purpose is to prevent a vehicle from starting if the driver has a blood alcohol concentration (BAC) above a pre-set limit. Attempting to bypass or cheat this system by having someone else blow into your interlock is not only illegal but also comes with severe repercussions that far outweigh any temporary convenience. The risks extend beyond just the primary user, potentially affecting anyone involved in the circumvention.

The Immediate and Lasting Consequences

If you allow someone else to blow into your interlock, the device's sophisticated technology is designed to catch it. While a sober person may successfully start the car initially, it's not a permanent solution and will inevitably lead to a recorded violation. This act of circumvention is considered a breach of your court or administrative order, triggering a chain of penalties that can significantly worsen your situation.

Detection Methods for Circumvention

Modern ignition interlock devices are not simple breathalyzers. They are equipped with multiple anti-tampering features to ensure compliance and accurately report any violations. The following features are common across many devices and ensure that attempts to cheat the system are unsuccessful:

Rolling Retests: After the vehicle is started, the IID requires random breath samples while the engine is running. If the owner is intoxicated and had a sober person provide the initial sample, they will almost certainly fail or miss a rolling retest, logging a violation.
Integrated Cameras: Many states now require interlock devices to be equipped with small, windshield-mounted cameras. These cameras snap a photo every time a breath sample is provided, creating a visual record for monitoring authorities and verifying who is actually taking the test.
Specific Breath Patterns: Some devices require a specific breathing pattern, such as a combination of blowing and humming, to prove a human is providing the sample and prevent the use of compressed air.
GPS Technology: Advanced units may come with GPS to record the location of all breath tests, providing another layer of tracking for authorities.
Tampering Sensors: Any attempt to physically damage or disconnect the device will trigger an immediate lockout and log a violation that is reported at the next service check.

Penalties for the Vehicle Owner

For the person required to have the interlock device, a recorded violation from a circumvention attempt has serious ramifications. These include:

Extended IID Requirement: The court or monitoring authority can extend the period you are required to have the device installed, potentially for months or even years.
Suspension or Revocation of License: Your restricted or conditional license can be suspended or revoked, forcing you to serve out the entire suspension period without any driving privileges.
Fines and Fees: You may face additional fines and legal fees related to the violation.
Legal Consequences: Violating the terms of your court-ordered program can lead to more serious legal charges, which in some states may include jail time, especially for repeat offenses.
Violation Lockout: The device may enter a violation lockout mode, immobilizing your vehicle and requiring you to have it towed to a service center for a reset, incurring additional costs.

Penalties for the Person Assisting

It is also a criminal offense in many jurisdictions for someone to assist a restricted driver in circumventing their IID. The consequences for the assistant can be severe and may include:

Criminal Charges: Depending on the state, knowingly helping to circumvent an interlock device can result in a misdemeanor charge, which goes on their criminal record.
Financial Penalties: The person assisting may face significant fines.

Owner's Responsibility: An Unbreakable Standard

One of the most important aspects to understand is that the IID owner is responsible for any and all activity logged by the device, regardless of who is driving. If a family member or friend operates your interlock-equipped car and fails a test, that violation is your responsibility. This is why it is crucial to ensure that anyone who drives your vehicle is sober and fully understands how to use the device correctly. A camera-equipped device can help provide evidence that you were not the one who violated the terms, potentially mitigating some penalties, but the violation will still be logged and reported.

Comparison of Consequences: Owner vs. Assistant


Aspect of Circumvention	Consequences for the IID Owner	Consequences for the Person Assisting
Initiating Circumvention	Violation is logged and reported to authorities. Potential license extension, suspension, or revocation.	Can face criminal charges and fines for knowingly assisting in a violation.
Detection	Caught by rolling retests, camera evidence, or data logging during service checks.	Captured on camera and identified as the one providing the sample.
Legal Action	Faces penalties for violating a court order, potentially including fines and jail time.	Faces criminal charges and fines, depending on state law.
Device Lockout	Vehicle is immobilized, requiring towing and a service visit to reset, incurring extra costs.	Not directly impacted by the lockout, but their actions caused it for the owner.
Long-Term Record	Violation on record, affecting license status and potentially facing stricter supervision.	Criminal record from misdemeanor, depending on jurisdiction.

Conclusion

In short, attempting to have someone else blow into your interlock is a high-risk, low-reward gamble that will be detected and reported. The technology is simply too advanced to be fooled by such a simple ruse. The consequences for the IID owner are severe, including extended mandates, license suspension, fines, and potentially jail time, while the person assisting may also face legal trouble. The safest and only compliant approach is for anyone driving the interlock-equipped vehicle to be sober and use the device as intended. Adherence to the program is not only a legal requirement but also a crucial step toward ensuring public safety and successfully completing your mandate. For more detailed information on specific state regulations, you should consult your monitoring authority or legal counsel, as requirements can vary.

Frequently Asked Questions

No, this is a serious and reportable violation of your interlock program. While it may start the car, modern devices include rolling retests and other features to detect such circumvention attempts, leading to severe penalties.

Modern interlocks are equipped with advanced technology to prevent circumvention. This includes requiring rolling retests while the car is in motion, using integrated cameras to photograph the person providing the sample, and logging all data for review by monitoring authorities.

The device owner is responsible for all activity logged. If another person driving your vehicle fails a test, that violation will be logged against your record and reported to your monitoring authority, leading to consequences for you, the owner.

Yes. In many jurisdictions, knowingly assisting a restricted driver in circumventing their interlock device is a criminal offense, potentially leading to misdemeanor charges and fines for the person who helps.

No. Attempting to disconnect or tamper with the device will immediately trigger a lockout, log a violation, and result in immediate reporting to your monitoring authority. This leads to serious penalties and requires the vehicle to be towed for service.

A rolling retest is a feature that requires a breath sample at random intervals while the vehicle is in motion. This prevents an intoxicated driver from having a sober person start the car and then taking over, as they will be required to provide subsequent samples.

Not all states mandate cameras, but they are becoming increasingly common. Many states require devices with cameras to verify the identity of the person providing the breath sample, with the photos being stored and reviewed for compliance.