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Texas Penal Code and DWI

If you're facing a DWI charge in Texas, it can be scary. The Texas Penal Code can be confusing, and it's written in hard-to-understand legalese. So, here we'll break down the Texas Penal Code and how it works with respect to the most common DWI charges.

Purpose of the Penal Code in Texas

While it often seems as if criminal laws exist simply to punish people for bad behavior, there is a higher purpose to these laws. The Texas Penal Code states, "The general purposes of this code are to establish a system of prohibitions, penalties, and correctional measures to deal with conduct that unjustifiably and inexcusably causes or threatens harm to those individual or public interests for which state protection is appropriate." Tex. Penal Code § 1.02 (1994). But the Texas legislature goes on to explain that the Penal Code should ensure public safety by:

  • Deterring bad or criminal behavior through penalties,
  • Rehabilitating those convicted of crimes, and
  • Preventing the recurrence of crime.

Having a detailed criminal code also lets all Texans know what behavior the state specifically prohibits and ensures that law enforcement officials don't arbitrarily punish legal behavior as criminal behavior. In this way, the Penal Code also protects all law-abiding citizens from unjust punishment. The Code also sets forth penalties for breaking the law, ensuring that punishments are fair, proportionate, and applied equally to everyone under the law.

In specifically laying out criminal behavior and possible penalties, the Texas Legislature also helps guide Texas law enforcement. The Code limits the police's discretion in arresting and charging Texas citizens, preventing “arbitrary or oppressive treatment" of people suspected, accused, or convicted of Texas crimes. Id. § 1.02(6).

History of Texas DWI Statutes

Texas hasn't always had a statute expressly banning driving while intoxicated. New York was the first state in the U.S. to pass a DWI law in 1910, followed by California and a few other states. But these early laws didn't define a specific blood alcohol limit until the invention of the "Drunkometer" in 1936. Robert Borkentein's early breathalyzer invention led to the American Medical Association's recommendation of a .15% blood alcohol content (BAC) limit.

By the 1970s, states began to introduce "per se" laws where the state didn't need to show that a driver couldn't properly operate a vehicle, only that the driver's BAC was over the legal limit. Texas's current DWI law still contains elements of this "per se" law.

The Texas legislature lowered the legal BAC limit to .08 in 1999. Not all of the country followed suit right away. It wasn't until President Bill Clinton's 2000 transportation appropriations bill that the rest of the country joined Texas. The 2000 transportation bill required all states to adopt a .08% BAC minimum by October of 2003 or lose federal highway construction funds. By July of 2004, all state legislatures had introduced the .08% BAC limit into their DWI legislation.

Explaining Texas DWI Statutes

People express a great deal of confusion about what constitutes "driving while intoxicated" in Texas. Part of this confusion stems from the two-part test outlined in the Texas Criminal Code and penalties that can arise from aggravating factors.

Driving While Intoxicated

To be found guilty of DWI in Texas, you must be operating a vehicle while either:

  • Impaired, meaning you don't have the "normal use of mental or physical faculties" because of alcohol or drugs, or
  • Have a BAC of .08% or higher.

As you can see, the police don't need to show that you were driving unsafely if your BAC is above the legal limit. Alternatively, the police can still arrest you for driving while intoxicated with a BAC below .08% if, in their judgment, you don't have the normal use of your faculties while driving. However, this is a subjective test, and your attorney can challenge it in court.

The Texas DWI statute doesn't state how the police should measure BAC. However, they generally use a breath or blood test administered by a trained technician. Because police must conduct these tests under strict technical and legal procedures, your attorney can also challenge these in court. No test is infallible.

A first DWI offense is a Class B Misdemeanor with a minimum penalty of 72 hours in jail, on top of fines, possible license suspension, and administrative penalties. But aggravating circumstances, such as a BAC over .15%, or open containers of alcohol in the car, increase penalties. Of course, multiple DWI offenses also increase jail time, fines, and administrative penalties.

Felony DWIs

Some aggravating DWI factors can increase the charge to a felony DWI in Texas. These include:

  • DWI with a Child Passenger: Driving while intoxicated with a child under the age of 15 in the car is a state jail felony in Texas. Tex. Penal Code § 49.045 (2003).
  • Intoxication Assault: Intoxication assault occurs when an intoxicated driver causes "serious bodily injury" to someone else. "Serious bodily injury" means having a high risk of death or causing permanent disfigurement or impairment. Tex. Penal Code § 49.07 (2007).
  • Intoxication Manslaughter: Intoxication manslaughter occurs when an intoxicated driver causes the death of someone else accidentally. Tex. Penal Code § 49.08 (2007).

While the Texas Penal Code sets forth the basic penalties, fines, and administrative penalties resulting from a DWI charge, there can also be additional repercussions. A DWI charge can affect custody of your children, professional licensing, security clearances, and even your ability to get a loan or rent an apartment. If you face a felony DWI charge, the long-lasting consequences can be even more severe. As a result, you need an attorney who has experience in DWI defense.

Contact Our Harris County DWI Defense Attorney

Attorney Doug Murphy is Board Certified in DUI Defense by the National College of DUI Defense (NCDD), accredited by the American Bar Association and the Texas Board of Legal Specialization. He is one of only two attorneys in the entire State of Texas who are Board Certified in both DWI Defense and Criminal Law.

Best Lawyers in America has also recently named Doug the "Lawyer of the Year" for DWI defense. Doug received this prestigious ranking through the peer reviews of his fellow Houston-area lawyers. There is a reason why the Houston Press named Doug Murphy the "drinking driver's best friend." Call us at 713-229-8333 today or contact us online to set up a consultation.

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