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False Positives and IIDs

Posted by Christopher Martens | May 15, 2015 | 0 Comments

As part of your DUI sentencing, you may be ordered to install an Ignition Interlock Device, or IID, in your car. If you were charged in Alameda, Los Angeles, Sacramento or Tulare counties, you will be automatically ordered to install an IID under the Ignition Interlock Device pilot program. IIDs are devices you have installed in your car ignition. They require you blow a breath sample in order to start your car and periodically, called a rolling retest, while your car is running. If there is any alcohol detected in your breath, your car will not start or, if you do not pull over to do your rolling retest and the IID detects alcohol in your breath, will honk the horn and flash the lights until you turn the car off. The IID will give you enough time after requesting the sample for you to safely pull over. In theory, IIDs work very well and prevent impaired people from driving, keeping California roads safer. They are however, like other computerized devices, subject to malfunction, failure and false positives. Also, because alcohol is an actually very useful chemical in many household items, the IID may detect alcohol in your breath but it doesn't necessarily mean you have been drinking alcohol. Alcohol is also a common byproduct of mixing other chemicals so things like foods and non-alcoholic drinks can result in false positives if combined with the right things. You should be given an orientation when you have an IID installed that shows you how to operate it. You may have been told to rinse your mouth with water before every sample and to wait 15 minutes between using alcohol-based mouthwash and blowing a sample. This can prevent alcohol present in your mouth from being read as a false positive. This amount of time and rinsing your mouth will not clear alcohol from your breath if you have actually been drinking alcohol. It is important to know what may cause a false positive because all failed tests are logged. Too many false samples will cause a lock out at which point you may have to wait or call the provider to be able to take the test again. IIDs set to detect hydrocarbons in general will produce many more false starts than those programed to just detect alcohols. With the general, i.e. non-alcohol specific IIDs, many things can give you a false positive. Eating spicy foods immediately prior to blowing your sample can cause a false positive. The spices mix with the acids in your stomach to produce methane gas, which may be detected. Other hydrocarbons present in your environment will do so as well but these devices are not the norm for DUI offenders. There are some myths regarding alcohol in your environment that can cause a false positive. Gasoline and alcohol-based perfumes and cosmetics in the air in your car are not concentrated enough to cause a false positive through a breath sample. Even with the alcohol-specific IIDs, potential false positives can come from a variety of circumstances. Most of these can be avoided by following a few simple rules: wait 15 minutes after using alcohol based mouthwash or spray before blowing your breath sample; or, use non-alcohol based mouth products; rinse your mouth out with water prior to every test, especially after eating or drinking anything other than water and clear your lungs and mouth of any smoke prior to every test. Remember to wait at least an hour following the consumption of any alcoholic beverage prior to blowing a breath sample. Following these rules will prevent most false positives from occurring when using alcohol-specific IIDs. Remember that all failed tests are logged, regardless of the source of alcohol, so take the extra steps to avoid false positives to begin with. Tampering with or otherwise circumventing the functions of the IID can result in penalties and it is illegal to have someone else blow the breath sample for you so your best bet is to follow the recommended procedures for using your IID.

Have you been charged with a DUI and need to install an IID? Contact Visalia area attorney Christopher Martens and his legal team. Experienced in DUI defense in Fresno, Tulare and Kings counties, our team will listen to your story and make sure you receive the best defense advise. Call our office at 559-967-7386 or email us at [email protected] for a free consultation.

About the Author

Christopher Martens

Bio Visalia and Bakersfield criminal defense attorney who has dedicated his life to helping those who have been accused of crimes or injured due to the negligence of others.


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