Texas DWI Ignition Interlock Laws

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In 2015, Texas Governor Greg Abbott signed new legislation that overhauled several Texas DWI laws regarding ignition interlock devices.

Specifically, this new legislation restricts any person whose driver’s license has been suspended for DWI to only driving a motor vehicle when an ignition interlock device is present.

While, at first glance, Texas’ DWI ignition interlock law seems restrictive, it has actually made it easier for a person convicted of DWI to drive during their license suspension.

What is an Ignition Interlock Device?

An ignition interlock device, or IID, is a device designed to prevent a driver from starting a motor vehicle if they’ve been drinking. Essentially, upon startup of the vehicle, the IID blocks the signal from the ignition to the starter until the driver provides a breath sample. This is done by blowing into a small handheld unit located near the driver’s seat. If the device detects no alcohol, the engine starts normally. If alcohol is detected, the vehicle will not start.

In addition, the device will randomly ask the driver for a breath sample while the vehicle is in operation. If alcohol is detected, the vehicle will not stop, as this could be unsafe. Instead, the IID will warn the driver to pull over and stop the vehicle. If this is not done, an alarm will be given by having the headlights flash on and off or the horn sound. This will continue until the vehicle is stopped.

It should be noted that all breath samples given by the driver are logged and are accessible to the court. This means that if the driver has been drinking and attempted to operate the vehicle, they will face additional penalties.

Finally, the IID is equipped with a camera. This ensures that the person giving the breath sample is actually the driver and not another person.

How Does Texas’ Ignition Interlock Law Work?

Prior to the enactment of the new legislation, a person who had their license suspended following a conviction for DWI was unable to drive. The only exception was to petition the court for an occupational license.

The process of obtaining an occupational license was complicated. The driver had to wait a specific amount of time before applying for the license. They also had to demonstrate to the court that driving was essential to their employment or schooling. Even then, the petition could be denied if it was in the best interest of public safety to do so. In addition, even if the petition was granted, the ability to drive was limited to a certain number of hours per day and on certain days of the week.

This complicated process meant that some drivers convicted of DWI continued to drive despite the license suspension. In short, the law, as written, was not doing what it was supposed to do.

Today, if a person is convicted of DWI and has their license suspended, they can still drive as long as:

  • This was their first DWI;
  • Their blood alcohol concentration, or BAC, was less than .15; and
  • their vehicle has been equipped with an IID.

They no longer have to wait to petition the court for an occupational license and hope that the judge finds that driving is essential to their employment of schooling. All they have to do is have the IID installed at their own expense and provide proof of this to the court.

A driver convicted of a first time DWI with a BAC less than .15 is not required to install an IID. They have the option of refusing the device and accepting a hard license suspension instead. This option is not available to drivers with a second DWI conviction within ten years of the first conviction or drivers whose BAC was .15 or greater. These drivers will be required to have an IID installed on their vehicle.

For a first time conviction, the process of getting an IID installed so that you can drive is fairly straightforward.  The court enters an order limiting a driver to operating only a motor vehicle equipped with an IID. A copy of the order is then sent to the Texas Department of Public Safety. The DPS then sends notice to the driver that their regular license has been canceled. This cancellation is effective 30 days from the date the notice is sent.

Before this 30 days is out, the driver must have an IID installed on their vehicle by a DPS-certified installer.  The DPS keeps a list of certified IID installers in the State of Texas. In the Dallas area, either Smart Start or Drager are good choices for having an IID installed. Both are nationwide companies who specialize in the installation, calibration, and monitoring of IID devices.

The cost of an IID varies by a number of factors, including the make, model, and year of the vehicle involved and the amount of time the IID will remain installed. MADD has estimated that, on average, an IID costs between $70 and $150 to install and between $60 to $80 a month to monitor and calibrate.  Under Texas law, if the court determines that a driver cannot afford to pay for an IID, it may impose a payment schedule that does not exceed twice the period the driver has to have the IID installed.

Once the device is installed, the driver can then apply to the DPS for a restricted interlock license by submitting the required paperwork and paying the appropriate fees.

The State of Texas takes driving while intoxicated seriously. This means that you need to take any DWI charges pending against you seriously as well. If you need an IID installed in order to drive, you want to make sure the process is done correctly. R.J. Harber is an expert in Texas DWI laws, and his practice focuses on DWI and DUI cases. Contact him for a free, confidential consultation at 214-389-1189, or through his online contact page.