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Interlock Ignition Device (IID)

An Interlock Ignition Device, or IID, is a small breathalyzer that is mounted on a vehicle’s steering wheel column and is electronically connected to the vehicle’s ignition. The IID is used by drivers who blow breath into the device via connected hose. If the device registers alcohol on the driver’s breath the vehicle will not start.

Is IID Required: An Interlock Ignition Device is not required by law for anyone who has not committed an alcohol related driving offense (DUI). A person may have an IID installed in her vehicle to prevent anyone from driving her vehicle with any amount of alcohol on the driver’s breath. On the other hand, if the driver was convicted of a drunk driving crime then an IID must be installed on any vehicle that the driver drives unless the driver would rather suffer the traditional driving penalties related to a DUI related offense.

License Suspension: An Interlock Ignition Device may be installed in a driver’s vehicle to avoid the traditional driver’s license suspension associated with driving under the influence of alcohol crimes (DUI). Prior to 2019, when a driver’s license was suspended for DUI the suspension was no less than thirty (30) days for a first time DUI offense. After the thirty (30) days the driver may elect to have a restricted license or continue the suspension. The suspension period for a first-time DUI without a restrictive period was four (4) months and the restrictive license period was five (5) months if the driver elected to have his suspended license restricted. The restricted driver’s license was restricted to allow the driver to drive only to DUI programs and work related driving. This is the traditional license suspension for DUI related crimes.

Post 2019 Law: After 2019, a driver who has her license suspended may elect to have an interlock ignition device installed in her vehicle, and thereby avoid any suspension or restrictions to her driving. With an IID there is no suspension period and no restrictions as to where the driver may drive. However, some driver’s may not be entitled to an IID option (depending on his or her criminal and/or DMV record).

Rolling Retest: Once a driver has started her vehicle the Interlock Ignition Device will require the driver to blow into the IID periodically. If the driver either registers alcohol on the driver’s breath during a rolling retest, or if the driver does not blow into the device when promoted to, the IID will register those actions. Rolling retest occurs about every fifteen minutes while driving; the driver will have about five minutes to blow into the device from the time the driver was prompted to retest.

IID Test Results: The results of the driver’s breath test, or failure to test when prompted, are registered in the IID itself. The test results may be sent to the Department of Motor Vehicles (DMV) for analysis. If the driver fails a breath test or fails to take a breath test when prompted by the IID the DMV will automatically reinstate the driver’s license suspension (with limited exceptions). Also, the DMV may send the electronic results of the driver’s blood alcohol concentration (BAC) to the district attorney for DUI prosecution.

Note: Failure to register zero alcohol on the driver’s breath will result in the vehicle failing to start. However, once the vehicle is started, if the driver fails to take a breath test when prompted by the IID, or if she registers alcohol on her breath, the vehicle will not shut off as that would be dangerous. Also, an IID is not available for DUI crimes that only involved drugs (Driving under the influence of drugs).

IID Duration: An Interlock Ignition Device is not available in all DUI cases. When the IID option is available the length of time that the driver must keep the IID installed depends on the number of prior DUI convictions the driver has suffered and/or the length of time ordered by the DUI criminal court. In most cases, the length of time an IID must be installed on the driver’s vehicle is as follows: First DUI offense (6 months); second DUI offense (1 year); third DUI offense (2 years); fourth and subsequent DUI offense (3 years). The criminal court may order an IID to be installed for a longer duration where the defendant failed a test.

IID Tampering: A driver who attempts to circumvent the IID or tamper with the IID will have her suspension immediately reinstated and the DMV will refer the evidence to the district attorney for a criminal prosecution of Tampering with an Interlock Ignition Device (VC 23247). Tampering with an IID includes the attempt to remove or bypass the device, including, but not limited to having another person blow into the IID, using a balloon to press "clean" air into the device, or any other type of technique designed to circumvent the IID’s purpose or function.

Installation and Fees: An Interlock Ignition Device cost about $70 dollars a month on average (depending on what IID company the driver uses). The driver is responsible for the IID fees but the installers are required to offer reduced fees to participants whose income level falls below set guidelines (sliding scale fees available). After installing the IID, the IID installer will provide the driver with an original Verification of Installation of an Ignition Interlock Device (DL 920 Form) to file with the DMV and criminal Court. The IID must be regularly calibrated and inspected. This means that the driver will be required to return to the installer every 30-60 days for this purpose. The IID information and results of breath test will be downloaded and logged for the DMV at that time.

Note: A driver ordered to install an IID must not drive a vehicle other than the vehicle(s) that have an IID registered to the driver installed. Also, a California order to install and drive with an IID is enforceable even when the driver drives out of state.

To learn more about Interlock Ignition Devices, DMV license suspension, or DUI defense, contact our experienced DUI lawyers today for a free consultation. Our DUI lawyers have successfully handled hundreds of misdemeanor and felony DUI and DMV charges in the Inland Empire, including the counties of San Bernardino and Riverside. Call today!


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