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    Ignition Interlock Supervision

    If you are charged with a DWI, you may be ordered by the judge or magistrate to install an ignition interlock device on your vehicle and to report to the Pretrial Services Office for verification of installation and monitoring of the interlock device.

    An ignition interlock device is a breath alcohol analyzer that is installed to a motor vehicle ignition. In order to start the motor vehicle engine, a driver must blow a breath sample into the analyzer which measures alcohol concentration. If the alcohol concentration exceeds the startup set point on the interlock device, the motor vehicle will not start (Title 37 Texas Administrative Code Rule 19.21).

    Ignition interlock supervision

    If you have been released from jail with orders for ignition interlock device installation, please report to the Pretrial Services Office on the assigned date with proof of installation and the $10 monthly supervision fee.  The device must be installed with proof of installation by the given deadline date (within 30 days from the date of release from custody).

    After the initial report, you will be required to report monthly to the DWI Ignition Interlock Officer with verification of calibration. You will be required to pay a $10 monitoring fee each month. ALL FEES MUST BE PAID BY MONEY ORDER.

    The Pretrial Services Office is located in the Tarrant County Corrections Center, 100 North Lamar St., Fort Worth, TX 76196.  Enter the building from the Belknap Street entrance.  Interlock Supervision is Monday through Friday, 7 a.m. - 7 p.m. and Saturday, 8 a.m- 5 p.m. APPOINTMENTS SUGGESTED.  You may call the office at 817-884-1465.

    ANY AND ALL violations will be reported by the DWI Ignition Interlock Officer directly to the court of jurisdiction. 


    County Telephone Operator 817-884-1111

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    100 E. Weatherford, Fort Worth, Texas 76196