The Ignition Interlock Device (IID)

DUI/DWI offenders may sometimes be required to install an Ignition Interlock Device  (IID) which will prevent them from operating the vehicle if their blood alcohol concentration (BAC) is above a predetermined limit.

Some states require the installation of an ignition interlock device in your vehicle if you are convicted for DUI/DWI. The exact law on ignition interlock device varies from state to state. While in some states it is mandatory, in some states the courts have the discretion to order the installation of the device. The state law will determine the time period for which the device must be installed in the vehicle.

State laws

In some states, the judges have the discretion to order the installation of an ignition interlock device (IID) depending on the circumstances of the case. In some states, the device is installed for the period of driver’s license suspension. If an ignition interlock device  is installed on your vehicle for the period of the  license suspension, you may still be able to drive if you meet other sentencing requirements such as completion of jail term, payment of fine, attending an alcohol treatment program, etc.

In other states, the judge does not have the discretion to order the installation of the device. It is mandatory. While it is generally not used in the case of a first time offender, states with mandatory ignition interlock laws require the installation of the device in case of multiple offenders or when there are aggravating factors present at the time of the DUI/DWI arrest such a very high blood alcohol concentration or presence of a minor in the vehicle.

How the Ignition Interlock Device works

The ignition interlock device (IID) is a device that will prevent the vehicle from starting if the driver’s blood alcohol concentration is over a predetermined limit. This predetermined level will depend on the state law. Some states set this limit a little lower than the legal blood alcohol concentration limit of 0.08 percent. However some states have set this limit at 0 percent which means the device will not allow the vehicle to start if there is even a slight trace of alcohol in the driver’s system. Once the driver gets into the vehicle, he or she must blow into a handheld device connected to the ignition interlock device. The device will measure the driver’s blood alcohol concentration. If the blood alcohol concentration is over the predetermined limit, the vehicle will not start.

Tampering with the Ignition Interlock Device

Do not attempt to tamper with the device. It is an offense to tamper the device. You will be required to take the vehicle to a state approved service station for periodic check up of your vehicle to determine that the ignition interlock device fitted in your vehicle is functioning properly. If the service station detects any signs of tampering, they will report you and you will be subjected to further penalties if found guilty.

Cost of the Ignition Interlock Device

You must pay for the device and bear the charges for installation. No exceptions. If you do not install the device, you cannot drive your vehicle.

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