Understanding DUI Ignition Interlock Devices

People that have been arrested and convicted of a DUI will often be required to have an ignition lock device placed on their vehicle. These are sophisticated machines and there are several items to keep in mind for people that must live with these devices.

 

What is the device?

 

Technically speaking the device is a breathalyzer connected to the ignition switch of an automobile. The machine measures blood alcohol content (BAC) in a manner similar to the field sobriety machines used by police. The devices will prevent the automobile from starting until the intended driver has passed the BAC breathing test.

 

What is the acceptable BAC level?

 

Most machines will lock the starting device of the automobile if the BAC is higher than .02. This means that most people can indulge in a small amount of alcohol and still have the opportunity to operate a vehicle.

 

Costs Associated with the Device

 

The ignition lock device, also referred to as an interlock, must be purchased by the DUI offender. The cost to buy the equipment, have it properly installed, as well as the monthly maintenance fees is all the responsibility of the person convicted with DUI. Typical installation costs vary from $100 to $200 plus any applicable tax. The monthly fees range from $70 to $100. If the data contained in the device is downloaded to the court or to an attorney there is usually an additional fee for this service. A list of certified device providers can be obtained by contacting the National Highway Traffic Safety Administration (NHTSA).

 

Conditions that require Interlock

 

Each state has a different system for requiring an interlock machine. Some states will impose the device as punishment and as part of the probationary period for individuals after their first DUI arrest. Other states will not. However, the majority of states require some type of ignition lock device for all repeat offenders.

 

There are usually additional circumstances involved when a first time DUI offense is subject to the interlock. For example

 

• The arrested person refused to submit to a breathalyzer test.
• The BAC was excessively high.
• The person was involved in an automobile accident that caused the injury or death of another person.

 

Time Period for Device

 

Typically, people must keep the device on their vehicle for at least one year following their DUI conviction. In addition, the person may have to keep the interlock as a condition of reinstating their license.

 

Safeguard against Tampering

 

As expected, many people attempt to get around the use of the interlock. However, the developers of these devices have invented several safeguards to prevent motorists from bypassing the system. For instance, the device will lock the ignition if the person refuses to take the breath test and attempts to start the car. If someone tries to remove the device or disable it in some way, it will lock the ignition. A few manufacturers have introduced rolling retests to deter savvy drivers.

 

The rolling retest works in the following scenario. A convicted DUI offender goes to their vehicle after drinking. They know they will likely fail the breathalyzer test so they ask a friend to breathe into the machine for them. The friend passes the test and the car starts. However, at some randomly chosen time period, after the car has been running, the machine will require a new breath test. If the DUI offender fails this test the car will shut down and the ignition will lock.

 

Monitoring By the Device

 

The interlock system has an onboard computer that stores the history of the tests completed by the driver. This historical record can be retrieved either by printing or downloading to a computer. Most device providers have the ability to retrieve the information at 30 day intervals to provide to attorneys and the court. If the report shows violations by the user the court may impose additional punishment.

 

Successful Deterrent

 

Several independent studies have shown that the interlock device has worked well to reduce the number of drunken driving arrests. Compared to the traditional policy of merely suspending a person’s license, some studies have shown a 90% reduction in drunk driving. The devices have led to more offenders following the rules of the court and successfully completing their probation period with a reduced number of instances.