Ignition Interlock Device (IID)

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The installation of an ignition interlock device in a vehicle often has been required in order for a person to retain his or her legal Texas driving privileges after certain types of convictions for DWI (driving while intoxicated, also known as DUI or drunk driving).

In 2015, the Texas Legislature overwhelmingly passed and the governor signed House Bill 2246. The new law, enacted Sept. 1, 2015, amends portions of several existing statutes. It allows a person who was arrested for DWI to obtain a restricted (or “hardship”) driver’s license if he or she installs and maintains an interlock ignition device (IID, also known as a deep lung device or DLD) in his or her vehicle before a DWI case is decided by a court.

The revisions to the statutes create a distinction between “essential needs licenses” prior to a DWI conviction and “occupational licenses” after a DWI conviction and make it a bit easier for a driver to retain driving privileges before a DWI case is resolved. In the past, an administrative license revocation (ALR) hearing was always required — with a relatively short time of only 15 days after an arrest to request such a hearing — and a restricted license was far from guaranteed.

Interlock Ignition Devices Defense Lawyer in Denton, Frisco, Lewisville, Flower Mound, TX

Texas law had already allowed for a person to seek an occupational driver’s license after a DWI conviction. Now a person may be able to retain his or her driving privileges throughout the DWI process — although nothing is guaranteed under the new law either.

The revised law also removed the requirement that a person seeking a (post-conviction) occupational license must state the reasons he or she is seeking a restricted license (such as to get to work or to transport children to school); now only proof of financial responsibility and proof of IID installation is required.

In addition, a person with an occupational driver’s license is not restricted to driving solely for occupational purposes if an IID is installed in his or her vehicle, which is not as harsh as the previous law.

If you were arrested for DWI, or convicted of DWI, in Denton, Texas, or anywhere in Denton County and are required to install an Interlock Ignition Device, you should consult with an experienced DWI attorney to learn about the details of the new IID requirements.

The Law Offices of Richard C. McConathy serves clients throughout Denton County, Texas, including the cities of Denton, Lewisville, Little Elm, Flower Mound, Grapevine, The Colony, and many nearby communities throughout the North Dallas area. Contact us today at (940) 222-8004 to schedule a time to meet with us during a free, confidential consultation with one of our skilled DWI attorneys. 

interlock ignition device

What is an Ignition Interlock Device?

The Texas Transportation Code, Title 7, Subtitle B, Chapter 521, Subchapter L, Section 521.241 states that an “ignition interlock device means a device that uses a deep-lung breath analysis mechanism to make impractical the operation of a motor vehicle if ethyl alcohol is detected in the breath of the operator of the vehicle.”

An IID is typically a handheld device connected to a vehicle’s ignition system and mounted to a vehicle’s dashboard or console.

In order to start a vehicle, a person must blow a breath into an IID, which then determines if alcohol is present in the person’s breath. If no alcohol is detected, the vehicle is allowed to start. When a vehicle starts after the initial breath test, the IID is programmed to randomly test a driver’s breath while in transit, a so-called “rolling test.”

If any alcohol above the low preset level is detected (including during a rolling test), the vehicle will be disabled and unable to start for a designated period of time. Repeated, failed breath tests may permanently disable the vehicle from starting, requiring a tow to the IID service center. Failing an IID test may result in the loss of driving privileges or a violation of probation.

What Offenses Require an Ignition Interlock Device?

Title 10, Chapter 49 of the Texas Penal Code lists DWI incidents in which a driver may be required to install an IID in his or her vehicle:

  • Driving While Intoxicated (DWI) — (most DWIs, except for certain first-time offenses)
  • Driving While Intoxicated with Child Passenger
  • Flying While Intoxicated
  • Boating While Intoxicated (BWI)
  • Assembling or Operating an Amusement Ride While Intoxicated
  • Intoxication Assault
  • Intoxication Manslaughter

Note: The Texas Code of Criminal Procedure, Title 1, Chapter 17, § 17.441 states that an IID is required for any subsequent DWI offense (after a first conviction).

Essential Needs Licenses

Texas law provides for an “essential needs” driver’s license for an arrest related to offenses under Chapter 49 of the state’s Penal Code after a DWI arrest, but before a DWI defendant appears in court for adjudication and during the period of an administrative license suspension.

Even if a person requests an ALR hearing within the required 15-day period after a DWI arrest and the request for a restricted license is denied, an essential needs license may be granted if a person provides compelling reasons why such a license is needed (such as driving to work or school), and agrees to install an IID.

Occupational Licenses

A person may be able to obtain an “occupational” driver’s license from DPS after a DWI conviction, even when his or her license would otherwise be suspended.

Under the new law, a person convicted of a first-time DWI offense no longer must provide a list of reasons why such a license should be granted but is required to show evidence of financial responsibility under Chapter 601 of the Texas Transportation Code and show proof that an IID was installed in his or her vehicle.

Note: An SR-22 insurance certificate was previously required for a person to drive with an occupational license, but under the new law an SR-22 is not required if “financial responsibility” can be shown.

A person who received an administrative license suspension is also usually required to attend counseling and treatment for alcohol dependence under § 521.245.

Fees Associated with Ignition Interlock Devices

In order to obtain a restricted interlock license (essential needs license or occupational license), a person must pay:

  • A fee of $10 to add the IID restriction to a driver’s license
  • The initial cost of installation of IID ($70 to $200)
  • Monthly fees for IID “rental,” maintenance, and monitoring ($50 to $100)

Additional Resources

Texas Transportation Code, Title 7, Subtitle B, Chapter 521 — Read the Texas statutes related to interlock ignition devices, occupational licenses and essential needs licenses.

Texas House Bill 2246 — Read the text of Texas House Bill 2246, which was approved and enacted into law in 2015. The bill changed the language of a handful of existing laws related to DWI and Interlock Ignition Devices.

Texas Department of Safety (DPS) — Read the official information about Ignition Interlock Devices on the DPS website, including an explanation of some of the fees associated with IID installation and maintenance, as well as information about certified IID service centers and driver eligibility status.

Find A Denton County Defense Attorney for DWI Charges | Law Office of Richard C. McConathy

If you were arrested for DWI or convicted on a DWI charge anywhere in Denton County, Texas, or any of the nearby communities and you are required to install an ignition interlock device on your vehicle, contact the Law Offices of Richard C. McConathy today to schedule a free initial consultation to discuss your case.

The experienced DWI attorneys at the Law Offices of Richard C. McConathy will be able to provide important information about all aspects of your DWI case, including the IID program,  how you may be affected by it, and what you must do to comply with it. We serve clients in Denton, Frisco, Lewisville, Flower Mound, and surrounding areas of Denton County, Texas.

Contact the Law Offices of Richard C. McConathy today at (940) 222-8004 to discuss your case.