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You Can Face DWI Charges Even for Prescription Marijuana

Updated: Sep 19, 2023 @ 5:14 am

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In 2015, Texas transformed its marijuana laws by passing the Compassionate Use Act, which allows certain individuals to receive medical marijuana. The state has amended the law twice, in 2019 and 2021, to expand the number of people who can participate. If eligible, a person can get certain cannabis products to help them manage pain.

However, having a card does not mean you can use marijuana or any cannabis derivative and then go out and drive. Cannabis has effects on a person’s nervous system, and you could be “intoxicated” under the definition of Texas DWI law. Please call Tad Nelson & Associates if you are arrested.

What is the Medical Marijuana Program?

Under the state’s Compassionate Use Program, doctors can prescribe low tetrahydrocannabinols cannabis, called THC cannabis, for certain medical conditions, including:

  • Autism
  • Amyotrophic lateral sclerosis (ALS)
  • Multiple sclerosis
  • Epilepsy
  • Incurable neurodegenerative diseases
  • Terminal cancer

Your doctor should register you in the Compassionate Use Registry. You can then go to any licensed dispensary to obtain your medication.

Marijuana Will Impair Driving

One unique feature of the Texas law is that the Compassionate Use Program only allows low-dose THC, and only in a form that can be swallowed, like gummies or lozenges. You can’t get marijuana leaves to roll into a joint to smoke.

Nonetheless, THC has certain chemical properties that can impair drivers:

  • Delayed reflexes
  • Impaired coordination
  • Distorted vision

Unsurprisingly, many people involved in accidents have used marijuana recently, and they struggle to control their vehicles. Even if they don’t crash, their erratic driving could draw the attention of police, leading to arrest and criminal charges.

Have Cities Decriminalized Marijuana?

In addition to legalizing medical marijuana, some Texas counties are pulling back on criminal enforcement of small amounts of marijuana. Harris County made waves in 2017 when it adopted a new diversion program. Anyone caught with up to 4 ounces of marijuana was diverted out of the criminal justice system and instead took a class.

Recreational marijuana remains illegal in Texas. However, lax enforcement will likely lead to more people using the drug recreationally. They do not fear getting arrested or suffering any type of criminal sanction for using small amounts of marijuana, which means some of them are likely to get behind the wheel of a car.

A Prescription Does Not Allow You to Drive

There’s some confusion when it comes to DWI and prescription drugs, including prescription marijuana. Some people wrongly assume that because they have a prescription it’s legal to drive. But that’s not the case.

Our DWI law specifically defines “intoxicated” to include not having normal use of mental and/or physical faculties because of a controlled substance or dangerous drug. Marijuana is a controlled substance in Texas, so you are legally intoxicated if you are impaired by it.

Furthermore, Section 49.10 says it is “not a defense” that you have a legal right to use the drugs. So the prescription does not provide any sort of defense.

Were You Impaired?

To be convicted, it’s not enough that you used marijuana. The state also must show it impaired your mental or physical faculties. Typically, they need to show you were driving erratically or dangerously. They don’t need to prove you got into an accident and hurt someone.

These cases depend heavily on eyewitness testimony, especially the arresting police officer, as well as dash cam footage. With alcohol, there is a certain BAC threshold which is defined as per se intoxicated. But there is no level for marijuana. Everything will depend on whether the prosecutor can convince the jury you were impaired due to any marijuana in your system.

How We Fight Back

At Tad Nelson & Associates, we have defended many “drug DWIs,” including marijuana cases. Getting caught with a joint on your dash is not an automatic conviction with jail time. We can take a full look at the evidence, including dash cam footage. You might have had passengers who can also testify that you weren’t driving dangerously. Sometimes the only evidence you didn’t have normal control of your faculties is the officer’s testimony that you drove over the center line.

Sometimes, police stop people for no reason. In that case, your entire encounter might be unconstitutional, and we can ask a judge to dismiss the charges.

Call for Help

Our DWI defense attorneys are available to discuss your case in a free consultation if you call. Don’t let one mistake send you to jail or interrupt your life. We have obtained successful resolution to hundreds of DWI cases in Texas.

Houston DWI Lawyer Tad A Nelson is Board Certified in Criminal Law by the TBLS.

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