The news circuit is abuzz with the DUI case of a woman who had her child blow into her Ignition Interlock Device to start the vehicle. She crashed with her daughter in tow and was charged with drunk driving once again. Some IIDs are equipped with cameras for the express purpose of preventing people other than the driver from blowing into it, and in one case the camera on an ignition interlock device helped catch a car thief red-handed. The devices, which use fuel cell technology to measure methyl groups (not liquor, per se), are a useful compromise between courts and the convicted, allowing an individual use of a restricted license on the condition that the device is installed in the car. Nevertheless, they're hardly a coveted automobile feature.

With drawbacks and advantages alike, one thing every driver and defense attorney should be cognizant of is the fact that sometimes IIDs fail, or report incorrect results. False positives can and have happened. False positives on IIDs have huge implications and possibly could lead to court subpoenas. The devices are not infallible. Here are some of the things that can yield a false positive on an IID.

1. Mouthwash - Mouthwash might be the most common culprit of false positives on IIDs because it is such a common household item. Mouthwash contains about 30% alcohol, the equivalent of or just under certain liquors. The IID is designed to detect any presence of alcohol, and since mouthwash evidently is detectable on your breath, it is primed to cause an issue. The presence of alcohol will begin to dissipate within 15 minutes and you can speed up the process even more if you rinse your mouth with water. It is generally a good habit to always rinse your mouth water prior to blowing into an IID. Your best bet is using nonalcoholic mouthwash to avoid the problem altogether.
2. Particular diets - Diabetics, people who are fasting, and people on a ketogenic diet are at risk of blowing a false positive on their IIDs. Anyone in a safety sensitive line of work (i.e. drivers, pilots) should likewise be aware that very low-carb or low-calorie diets create a high content of acetone in the blood, and this can yield a false positive. Even cinnamon rolls, due to their high yeast and sugar content, have been shown to produce false positives. You can usually rectify this by waiting at least 15 minutes before blowing into the device.
3. Spicy Food - When certain spices mix with the hydrochloric acid in the stomach, it can create methane which can trigger a false positive. Try to avoid eating directly before giving a sample of your breath.

The first step in combating false positives is knowing what can trigger an IID. A good rule of thumb is to avoid food or drink, or oral ingestion of any kind before blowing into an IID, but this isn't always possible.

If you have been charged with drunk driving as a first offense or because of an ignition interlock issue, contact the Seattle law offices of Steve Karimi at (206) 621-8777 or contact him online.