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Everything You Need to Know About Ignition Interlock Devices


An ignition interlock device (IID) is a handheld breath-testing device which connects to the vehicle’s ignition, horn, and headlights. In order to start the vehicle, a driver needs to blow into the device without registering a BAC.

In 2009, the Missouri Legislature instituted the ignition interlock law in order to prevent repeat DWIs. Any person guilty of a second or subsequent intoxication-related traffic offense to install an IID on any vehicle they operate before reinstating driving privileges.

For those with first-time DWI offenses, judges have discretion to impose ignition interlock for first-time offenses for over six months. First-time offenders can even choose to install an IID to reduce his or her driver’s license suspension time in half. If a driver installs an IID, he or she can then drive after 15 days of license suspension (on restricted driving privileges). The person’s driving privileges will be restricted for 75 days, after which the driver’s license will be reinstated.

However, IIDs require an installation fee, in addition to a monthly fee of $70 or more. Failure to maintain the IID can lead to license suspension for one year for the first offense and five years on a second offense.

If you were convicted of a DWI in Missouri and need to obtain a restricted license in order to commute to work or conduct day-to-day activities, contact our St. Louis criminal defense lawyer at The Hammer Law Firm today.

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