An ignition interlock device, or IID, is a mechanism installed in the dashboard of a motor vehicle. Designed for use by individuals convicted of driving under the influence (DUI), an IID measures breath-alcohol concentration and determines whether it exceeds a preprogrammed blood-alcohol concentration. If the measurement is over the threshold, the IID prevents the vehicle ignition from starting so the driver cannot operate the automobile.
DUI Arrest Penalties
Each state has different DUI laws but all states consider DUI a crime. Penalties for a DUI conviction include fines, license suspension, probation, and jail time. Additional penalties may include installation of an IID in the driver’s vehicle for a temporary period. A professional must install the device and the driver must pay both installation and monthly rental fees, increasing the financial consequences of the DUI.
An IID works by interrupting the signal between the car ignition and starter if a valid breath sample meeting the blood-alcohol guidelines is not provided. Drivers must provide breath samples at random times after successfully starting their vehicles, preventing other individuals from driving their cars. The IID records every invalid or unacceptable reading and issues a warning that includes an alarm. The vehicle must then be turned off until a valid breath sample can be provided.
The sensor on an IID is an ethanol-specific fuel cell. It subjects alcohol to a chemical oxidation reaction on a special catalytic electrode surface that generates electric current. The device measures the current and converts it to a reading that is alcohol-equivalent. Each time the sensor is calibrated, the activity log is downloaded or printed and may be reviewed by authorities.
When IID Installation is Required
Not all states require the installation of an IID, particularly for a first DUI conviction. Alabama, South Dakota, and Vermont DUI laws do not require IID installation, even for repeat convictions. In Texas, an IID is required in limited circumstances. The majority of states give courts discretion regarding IID installation and Arizona, Connecticut, Georgia, Illinois, Kansas, Louisiana, Michigan, New Mexico, and Pennsylvania include this potential penalty for repeat offenders only.
Talk to a DUI attorney to find out whether IID installation is a potential requirement in your state. Let the attorney review the case to determine whether pleading not guilty is a viable option. Fighting a DUI charge might require time and effort but these attorneys specialize in these cases and often emerge victorious so learn how they can help.