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IID: Ignition Interlock Devices

Technology is increasingly important when it comes to the enforcement of drunk driving laws. Blood alcohol concentration testers like Breathalyzers are often relied upon to support the issuance of, and conviction on, DUI charges, and ignition interlock devices are used in many cases to prevent any future drunk driving activity.

Ignition interlock devices (IIDs) are the subject of state statutes around the country. In some states, judges have discretion regarding whether or not to order the installation and use of an IID while in others, IIDs are mandatory under certain circumstances. Typically, if an IID is ordered or approved in a particular case, then the person convicted of drunk driving must bear the costs associated with the purchase, installation and maintenance of the device.

How an Ignition Interlock Device Works

An IID is a piece of equipment that is installed in a motor vehicle in order to prevent the vehicle's operator from driving while intoxicated. The device consists of a mouthpiece and an analysis unit that is attached to the motor vehicle's ignition system by a cord. The driver is required to blow into the mouthpiece prior to starting the vehicle.

When the driver blows into the mouthpiece, an analysis of the driver's blood alcohol concentration is conducted based on the presence of alcohol in his or her breath. The vehicle will not start if the driver's BAC is over a preset limit. The limit varies from state to state, but it is typically in the range of .02 to .04 percent. Breath test results from the IID are often stored and sent to a monitoring agency, like a probation officer, the court or the department of motor vehicles. In some states, the data is sent immediately to the agency, while in other states, the data may only be sent weekly or monthly.

In addition to requiring a breath sample prior to starting the car, IIDs in some states are programmed to demand retests randomly while the car is running. These "rolling tests" are designed to prevent a drunk driver from having a sober person blow into the unit to start the car or from starting the car and then drinking while driving.

State Laws - Discretionary IID

In some states, judges have some discretion regarding whether or not to order the installation of an ignition interlock device in a vehicle following a drunk driving conviction. The specifics of the particular case will determine whether the judge has that privilege. It is more likely that the issue will be up to the judge if the person convicted had a BAC only slightly in excess of the state's legal limit or if the facts of the case meet other parameters.

Some states also allow a person to install an IID and thereby obtain a restricted driver's license earlier than they would otherwise be allowed. In Mississippi, for example, a person who is convicted of drunk driving may in some cases be allowed to reduce the period of license suspension by installing an IID pursuant to Mississippi Code Section 63-11-31. California will give first-time DUI offenders an option regarding the installation of an ignition interlock device beginning in 2019.

Depending on the laws of the relevant state, the person who is convicted may have to meet certain sentencing requirements before he or she can drive with an interlock ignition device in place. Such requirements may include the passage of time, serving a jail sentence, paying fines, completion of a driver's license suspension or satisfactory completion of a treatment program.

State Laws - Mandatory IIDs

Many states have laws that make the installation of a car breathalyzer mandatory. While there are states with laws that call for an IID even after the first conviction, many mandatory IID situations involve a second or third conviction on DUI charges or other aggravating circumstances. In some states, an IID will be required for a first offense drunk driving conviction if the offender was driving with a minor in the car, and it is increasingly common for states to require IIDs in cases where the driver's BAC was greater than 0.15 at the time of the offense.

Many states require ignition interlock devices for second or subsequent DUI offenses. In Missouri, for example, the installation of an IID is discretionary for a first offense DUI conviction and mandatory for a second, third or later conviction. The relevant law can be found in the Missouri Revised Statutes Section 577.600.

In Arizona, a person who is convicted of drunk driving will be required to install an IID in any motor vehicle that he or she operates, even for a first offense, and it generally must be installed for a period of at least 12 months. The relevant law is contained in Arizona Revised Statutes Section 28-1381(I)(6) . Other states in which the installation of an IID is mandatory upon conviction of DUI charges include Delaware, Illinois and Kansas.

Paying for an Ignition Interlock Device

The laws that require or regulate IIDs vary widely from state to state. In most cases, the costs associated with the lease or purchase of the IID, as well as installation costs, must be paid by the person who was convicted of drinking and driving. The offender must usually pay any fees associated with monitoring or calibration as well. Some states may reduce fines to help an individual cover IID costs if the individual demonstrates that payment would present them with a significant financial hardship.

Speak to an Experienced Drunk Driving Attorney Today

This article is intended to be helpful and informative. But even common legal matters can become complex and stressful. A qualified drunk driving lawyer can address your particular legal needs, explain the law, and represent you in court. Take the first step now and contact a local drunk driving attorney to discuss your specific legal situation.

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