Former Municipial Court Judge

Former Assistant District Attny.

Denton County Office 940-580-2899
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Proposed Interlock Law for First Time DWI Offenders

Tim Powers

Law Office of Tim Powers


A new bill would require first time DWI offenders in Texas use an ignition interlock device on their vehicles. House Bill 189 states that judges may grant first-time offenders deferred adjudication, or delayed judgment on a charge, as long as the offender was not driving with a child younger than 15 and the offender did not injure or kill another person while driving. The new language from the statute requiring an interlock device says:

A judge granting deferred adjudication to a defendant for an offense under Section 49.04, 49.05, 49.06, or 49.065, Penal Code, shall require the defendant to have an ignition interlock device installed under Subsection (i), regardless of whether the defendant would be required to have the device installed if the defendant was convicted.

MADD is supporting the H.B.189, because it includes a section that requires a deferred adjudication be considered a conviction for purposes of enhancement of penalties. MADD had worked against previous legislation of this type, because they felt some repeat offenders would plead to a different offense, and avoid any record of the DWI charge.

How an Ignition Interlock Works:

  • An ignition interlock is electronic device that is attached to the vehicle's ignition and is typically installed on the vehicle dashboard. Before starting the vehicle, the driver first must exhale into the device. If the interlock detects alcohol on the breath, the engine will not start.
  • At random times when the engine is running, the device will require the driver to provide additional breath samples. If a breath sample is not provided, or the sample exceeds a set blood alcohol level, the device will record the event, warn the driver and then start up an alarm (lights flashing) until the ignition is turned off, or a clean breath sample has been provided. This is designed to prevent someone from having a sober person blow into the device, allowing them then drive away intoxicated.

Politically, legislators and strong lobby groups ganging up on first time DWI offenders is popular and gains attention in the media. However, it is our opinion that a requirement for and ignition interlock in all first DWI probations is overkill and counter-productive. Instead of the offenders being supervised by the State for up to 24 months, many will opt for a few weekends in jail, not be subject to probation and have no suspended sentence hanging over their head should one fail to complete all the conditions of probation. It's the judicial equivalent of using a bazooka to kill a cockroach, but missing the intended target and knocking down the wall instead.

If you are seeking aggressive criminal representation by an experienced criminal defense attorney for your Denton County DWI case or arrest in Denton County, contact the offices of Tim Powers today. There is no charge or obligation for the initial consultation. 940.580.2899.

*Tim Powers is an attorney licensed to practice law by the Supreme Court of Texas. Nothing in this article is intended to be legal advice. For legal advice about any specific legal question you should directly consult an attorney.