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Houston Marijuana DWI Defense Lawyers

Marijuana DWI Defense Attorneys in Houston, TX

While many states throughout the United States have legalized the medical use of marijuana, and more than a handful have legalized the recreational use of marijuana, Texas has mostly been steadfast against any legalization minus the Striking Oil 2015 Senate Bill 339, which came into effect September 1, 2017, and which allows patients who suffer from intractable epilepsy to use a low-THC cannabidiol oil for treatment. Most users of marijuana in Texas, however, are not epileptic; they are persons from all socio-economic backgrounds. And in 2017, there was bipartisan support for marijuana policy reform throughout Texas.

Though the momentum to legalize marijuana in some form or another grows, the end result will not affect DWI drug laws. Driving while impaired by any drug, illicit or otherwise, is illegal in Texas. Anyone who smokes marijuana, or consumes it in any other form, and operates a motor vehicle, can be arrested and charged with driving while intoxicated, even though they did not consume alcohol.

Effects of Marijuana & Impairment

The effects marijuana has on a person varies, but generally, the effects include:

  • Relaxation
  • Euphoria
  • Disorientation
  • Altered time and space perception
  • Drowsiness
  • Paranoia
  • Image distortion
  • Increased heart rate

All these effects can have an impact on a person's driving abilities because these effects can impair judgment, motor coordination, and reaction time. The latter three functions are necessary for safe driving. Studies, however, have produced mixed results. Other studies, including a controlled study by the National Highway Traffic Safety Administration, suggest there is no significant link between marijuana use and fatal crashes. You need a proven Board Certified DWI lawyer who knows how to utilize these studies and successfully cross-examine the expert witness on the 12-step DRE police tool to demonstrate no impairment due to marijuana inhalation or ingestion. It is only illegal to possess marijuana or THC products in Texas.

Marijuana & Texas DWI Law

According to Texas Penal Code Ann. § 49.04, a motorist can be charged with driving while intoxicated if they do not have the normal use of their mental or physical faculties by reason of the introduction of marijuana. By reason of its illegal status and the nature of the drug, the state will use any amount of marijuana found in the person's test specimen to try to prove he or she was driving under the influence (Texas Penal Code Ann. § 49.01). But there is no Texas law that indicates any level of marijuana or any of its active or inactive metabolites is per se illegal or a level that causes impairment.

Penalties for DWI in Texas are generally the same regardless of whether you were driving while intoxicated by alcohol, a prescription drug, or an illegal drug. Any former DWI conviction will be considered a prior for any new DWI conviction, regardless if the first DWI conviction was related to alcohol and the new DWI charge is related to marijuana or other drugs; they are all DWI offenses.

Penalties for DWI Conviction

1st Offense

2nd Offense

3rd & Subsequent

Minimum Incarceration

3 - 180 days

30 days - 1 year

2 - 10 years


Up to $2,000

(unless a child under 15 was in the car)

Up to $4,000

(unless a child under 15 was in the car)

Up to $10,000

License Suspension

90 days - 1 year

180 days - 2 years

180 days - 2 years

The above penalties can also be accompanied by additional penalties that include but are not limited to:

  • Community Service
  • Drug Rehabilitation/Therapy
  • DWI School
  • Vehicle Impoundment

If you have marijuana on your person, the officer may also attach a drug possession charge to your DWI marijuana drug charge. There are some jurisdictions in Texas (including Houston and Harris County) that no longer prosecute low-level marijuana possession, however, officers may use the possession to prosecute for driving while intoxicated (DWI) with marijuana. If you are found guilty of marijuana DWI, additional fines and jail time may apply in your sentence.

Proof of Marijuana Intoxication

Unlike driving under the influence of alcohol, there are no per se drug laws in Texas. In other words, we know that 0.08% blood alcohol content level is the legal limit of alcohol you can have while driving, but there is no legal limit if THC is found in your blood or urine sample. Further, there are no reliable methods to determine marijuana intoxication.

In fact, some courts in the U.S. have found that blood and urine samples are unreliable because the psychoactive component of marijuana (THC) is detectable in your system up to four or five weeks after it has been consumed, and no test can conclusively detect actual impairment at a given time. Field sobriety tests have even come under attack by courts, with the Supreme Court of Massachusetts finding that these tests, too, are unreliable for marijuana detection.

Drug Recognition Experts (DRE)

With courts finding tests unreliable to prove marijuana intoxication at the time of driving, police units have started training officers in drug recognition. The International Association of Chiefs of Police (IACP) has devised a training curriculum to qualify police officers within a few weeks as experts in drug recognition, naming these officers Drug Recognition Experts. Drug Recognition Experts are used by the prosecution in an attempt to prove you were driving while drugged. The DRE process was not created by doctors or scientists, rather it was created by two Los Angeles Police Department officers. The studies on DRE show that this 12-step DRE process is not reliable or accurate at predicting impairment by drugs.

If you are stopped, and the officer is a DRE and requests you submit to an evaluation, you should (1) not disclose any drug use, even if it is a legal drug for medical purposes; and (2) refuse to submit to the evaluation. The latter are not probable causes to obtain a warrant. There have been many cases of wrongful arrests throughout the United States when DREs have suspected driving while impaired by drugs, but no impairment existed. These so-called experts receive minimal training and then are released to "evaluate" suspected drivers. The evaluation is a 12-step process that the officer is to implement to determine drugged DWI.

12-Step DRE Process

There are twelve steps a drug recognition expert is supposed to put a driver through if the officer suspects DWI by marijuana or other drug intoxication. The evaluation is apparently supposed to help the DRE officer determine whether you are impaired, and if so, what category of drug impairs your driving capabilities. The 12 steps are:

  1. Breath alcohol test
  2. Interview with suspect
  3. Preliminary examination, which should include a determination of any medical conditions the suspect may have
  4. Eye exam, which includes the field sobriety nystagmus test
  5. Divided attention tests, which include the field sobriety one-leg stand and walk-and-turn tests
  6. Examination of vital signs
  7. Darkroom examinations, including pupil size
  8. Muscle tone examination
  9. Examination of common injection sites
  10. Consideration of statements and actions by the subject
  11. Opinion by DRE certified officer
  12. Chemical tests to determine the presence of drugs and/or corroborate the DRE officer's opinion.

The 12-step test will often be employed if the suspect passes a breath test, thus ruling out a DWI by alcohol but suggesting possible drug impairment. Though this training may help police officers in their determination of a drugged driver, it is not scientifically sound, and the lax regulation of their limited training creates a false sense of expertise. Some medical experts are raising the alarm about this issue. A DRE distinction does not translate into expert knowledge; the training and the evaluation are flawed and inherently subject to human error.

Things to Consider About Your DWI Drug Charge

A DWI drug charge can be an intimidating charge that may influence your actions to plead guilty and get the whole matter over. The problem is, though, a DWI conviction never really goes away. There are some things you should consider before you decide to enter a plea of guilty or not guilty.

  • Never enter a guilty plea to a DWI charge, and this is especially true if it is your first DWI offense. You need the facts before any plea is entered. An experienced attorney can assess your case and recommend if a guilty plea is the better option, but an experienced DWI attorney who has successfully represented hundreds of DWI cases throughout the greater Houston area will be able to provide a defense strategy that greatly increases your chances of a successful outcome. An experienced DWI lawyer will advise you of the factors that work in your favor or factors that do not work in your favor. Your attorney will always communicate what is best for you and your unique situation.
  • You should never assume because you are guilty of the offense that you cannot get out of a conviction. Experienced Houston DWI lawyer Doug Murphy will address your defense from different angles to maximize a successful outcome. Officers may have made mistakes in the process of your arrest, or other details may be present that impact your case to your benefit. As mentioned above, all the facts are needed before a real assessment can be made about the outcome of your case.
  • You should consider the consequences of a DWI drug conviction. The penalties allotted at court are tough, but it is the collateral damage that can be to your greatest detriment. A DWI drug conviction on your permanent record can have significant consequences for academic aspirations, school loan or scholarship applications, job hunting, professional licensing approval, and auto insurance premiums. These things can have a deep impact on the quality of your life and your ability to make a living.

Possible Defense Against a DWI Marijuana Charge in Texas

The stakes for a conviction of a DWI drug charge are high. A good defense may not produce an outcome you want, but an aggressive, prudent defense can. Defenses in DWI drug matters are highly dependent on the facts of the case, and only an experienced, board certified DWI lawyer like Doug Murphy will know how to devise a strategy that comprehensively defends your case. At Doug Murphy Law Firm, P.C., suspects of DWI marijuana charges are provided aggressive, comprehensive defense with the aim to compel dismissal or persuade a "not guilty" verdict.

Depending on the facts, there are several key strategies that DWI criminal defense attorney Doug Murphy may employ. The details of the facts will be important to the defense strategy. Specific questions to consider include:

  • Was there a reason for the police officer to stop your vehicle? If so, what was it?
  • Did the police officer ask you to perform a standardized field sobriety test? If so, which one(s), and was it administered properly?
  • After evaluating the cause to stop the car and the results of the sobriety test, was there probable cause to make the arrest?
  • Did the police make any mistakes?
  • If you refused a breath or blood test, was there justification for the refusal? If not, why did you refuse the test?
  • Are the test results reliable and accurate?

If you want to preserve your driving privileges, avoid expensive fines, prevent jail time, and maintain a clean record, then you should contact Texas DWI board-certified lawyer Doug Murphy.

Contact Our Houston, Texas Marijuana DWI Lawyer

Being arrested for driving under the influence of marijuana can be a terrifying experience, especially when you haven't even consumed marijuana for days. At Doug Murphy Law Firm, P.C., we devote our resources and capabilities to DWI cases. We have decades of proven experience and a reputation earned in the courtroom for successful results. Attorney Doug Murphy is a board-certified DWI lawyer who not only fights on behalf of his clients but constantly gives back to the legal community to teach other attorneys how to do the same. Contact us today at 713-229-8333 to discuss the circumstances of your case. You will need a lawyer who has routinely taught other lawyers how to successfully fight DWI with marijuana cases.

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