What Makes Ignition Interlock Devices Unreliable?

What Makes Ignition Interlock Devices Unreliable?
Feb 07, 2023 |

Interlock devices, also called Ignition Interlock Devices or IIDs, are installed in the vehicles of individuals who have been convicted of drunk driving offenses. The device requires the driver to provide a breath sample before the vehicle will start and if alcohol is detected on the driver’s breath, it will prevent the vehicle from starting. Here’s how IIDs can fail and how to get help after a DWI in Texas.

The Unreliable Science Behind IIDs.

An IID is installed in a vehicle to test the driver’s BAC before the car can start. If the device detects alcohol on the driver’s breath, it will prevent the car from starting. IIDs are supposed to reduce drunk driving, but they’re not foolproof. The devices can give false positives, which can prevent a sober driver from starting their car, and false negatives, which can allow a drunk driver to start their car.

Ignition interlock devices are designed to measure the breath alcohol concentration (BrAC) of drivers, but they cannot distinguish between two different drivers. This means that anyone can blow into the IID – not just the owner of the vehicle or the driver who is supposed to be tested. A sober person could blow for an intoxicated driver, who would then be free to operate the vehicle.


Several other methods exist to prevent drunk driving, which may be more effective than IIDs as a deterrent. Public education campaigns can serve as an effective tool in changing public perception of drunk driving and reducing the number of people who choose to drive while drinking or on drugs. Ridesharing services like Uber and Lyft can also deter drinking and driving by providing alternative transportation.

Parents can also play a role in educating their children on the dangers of drunk driving, and setting an example by not driving while under the influence. They can also ensure that their children are aware of the legal consequences of driving while under the influence, such as license suspension and hefty fines.

Were You Arrested For Drinking And Driving In Texas?

If you were pulled over for drunk driving, you need the help of an experienced Texas DWI attorney to fight the charges against you. A criminal defense attorney can also help protect a person’s rights and freedoms throughout the legal process and ensure that they are treated fairly by the court system, and can help to keep the fines, fees, and other costs associated with a DWI conviction to a minimum.

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