State of the Practice of Ignition Interlock Programs

Interlocks are an important countermeasure to prevent Driving While Impaired (DWI), defined as driving while having a blood alcohol concentration (BAC) of 0.08 grams per deciliter (g/dL) or higher. An interlock is an alcohol-detection device designed to prevent alcohol-impaired individuals from starting their vehicles if their breath sample registers a breath alcohol concentration (BrAC) higher than a pre-specified level. All states allow the use of interlocks as a criminal or administrative sanction for DWI. States manage interlock services through their state interlock programs. This research will examine States’ interlock programs with the goal of learning various strategies for administering programs, solutions to common issues, and promising practices. The research will seek information from interlock program administrators and staff to update an online inventory of interlock programs.

The latest form for State of the Practice of Ignition Interlock Programs expires 2022-06-30 and can be found here.

State of the Practice of Ignition Interlock Programs Online Questionnaire

Federal Enterprise Architecture: Transportation - Ground Transportation

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