Understanding ignition interlock devices: myths and reality

On Behalf of | Oct 27, 2021 | Drunk Driving |

One of the most used devices to enforce a drunk driving penalty in Michigan is the ignition interlock device (IID). While most Michiganders understand the basic operation of an IID, very few know how the law itself works and many people have accepted misleading and damaging myths about how an IID can be defeated.

What is an IID?

An IID is a device that can detect alcohol in a person’s blood stream. In this respect, an IID operates much like a breathalyzer or other device that uses a combination of chemistry and physics to determine the amount of alcohol in a person’s blood stream. An IID differs from a breathalyzer in one important respect: the IID is designed to be connected to a car’s ignition system and to prevent the car from starting if the driver has an excessive amount of alcohol in his blood stream. The IID must be installed by a qualified mechanic. Every time the person owning the car, assuming that the owner is the subject of the sentence requiring used of an IID, wishes to drive the car, he or she must blow into pipe that collects the person’s breath and transmits it to the portion of the IID that measures blood alcohol content (BAC). The car will not start if the IID detects a BAC above the court-specified limit. (Most courts order a BAC that is lower than the state’s maximum BAC for demonstrating intoxication.) The IID cannot be removed from the subject car without a court order. Doing so without first obtaining such an order is a crme.

Can another person take the IID test for the driver?

Attempting to substitute another person for the person subject to the IID requirement is illegal in Michigan, and attempting to have a substitute driver take the IID blow test can result in severe penalties being added to the initial sentence. Most current IID units capture a photograph of any person taking a blow test, and this photo can be used as conclusive evidence of an attempt to defeat the IID sampling measurement.

Will certain foods affect an IID test?

Some foods contain enough alcohol to register a positive test on an IID. The person taking the IID test should brush his or her teeth immediately before taking the test. Also, some foods contain alcohol from the cooking, and this provides another reason to clean one’s teeth after eating.

Anyone who has been ordered to place an IID on their car should seek advice from an attorney experienced in handling DWI cases. Hiring an aggressive and knowledgeable defense attorney as soon as possible may be the best method of avoiding an order directing placement of an IID on one’s own vehicle.