What are ignition interlock devices?

August 4, 2022
What are ignition interlock devices?

Ignition interlock devices are designed to minimize the risk of obtaining another DWI in Missouri once you have been convicted. According to the Centers for Disease Control and Prevention, ignition interlock devices decrease the number of repeat driving while intoxicated offenses by 70% when installed and used correctly.

Interlock devices allow drunk driving offenders to drive with a restricted license, even while their driver’s licenses are revoked. IIDs can help you get to work, school and/or run errands, all while staying compliant with the law.

How do ignition interlock devices work?

Interlock devices install directly into the ignition system of the vehicle. Before the vehicle will start, the driver must blow into a tube connected to a dashboard monitor. If the driver’s blood alcohol content level reads below a preset level, usually 0.02, the car will start. During the drive, the motorist must submit subsequent breath samples in order to keep the car going.

The IIDs record information, such as startup attempts, BAC levels, lockouts and tampering and reports directly to the law enforcement department.

When are interlock devices required?

In Missouri, and in many other states across the nation, interlock devices are required for everyone convicted of a DWI, including first-time offenders. Once the offender’s driver’s license is reinstated, interlock devices are required for at least six months.

Furthermore, the vehicle must be brought in for routine maintenance appointments. During these appointments, technicians calibrate the devices, ensure they are working property and download information to send to the law department.

If you have been charged or convicted of a DWI, it is critical that you understand how IIDs work. This information may help reduce the risk of reoffending and help you get your life back on track.


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