While many people associate a DWI charge with driving under the influence of alcohol, it is possible to be arrested and charged for a DWI because police suspect you of being under the influence of another substance, whether it is a controlled substance or a prescription medication, including marijuana.
Intoxication is defined by in Texas Penal Code § 49.01(2)(A) as “not having the normal use of mental or physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, a dangerous drug, a combination of two or more of those substances, or any other substance into the body,” or having a alcohol concentration (BAC) level of 0.08 or above.
Being under the influence of marijuana can lead to a DWI charge if the prosecution can prove that you were driving a motor vehicle or in actual physical control of a vehicle and did not have normal use of your mental or physical faculties due to being under the influence of marijuana.
Effects of Marijuana
Marijuana can cause some of the following physical and mental effects:
- Distorted perception
- Increased heart rate
- Increased appetite
- Eye redness
Marijuana DWI Investigations
If police pull you over during a traffic stop and suspect that you are driving while under the influence of marijuana or another intoxicating substance, they may ask you to perform a series of field sobriety tests and may request that you submit to a urine or blood test. Police may be able to request a warrant for a blood test if you refuse to provide a sample of your breath or urine.
If investigating officers need additional evidence regarding your impairment by a substance other than alcohol, they may ask you to submit to an examination by a drug recognition expert, or "DRE" which is a law enforcement officer who has received training and certification to look for signs of impairment by substances other than alcohol.
Penalties for Marijuana DWI in Texas
Penalties for a marijuana DWI in Texas are the same as those for driving while intoxicated based upon alcohol. The penalties increase if you have been convicted of DWI charges previously, whether you were convicted of driving while under the influence of alcohol, marijuana, or another substance. The penalty ranges are as follows:
- First Offense – 3 to 180 days jail, up to a $2,000 fine, and license suspension for up to one year
- Second Offense- 30 days to 180 days jail, up to a $4,000 fine, and license suspension for 180 days to 2 years
- Third or Subsequent Offense – 2 to 10 years in a Texas state correctional facility, up to a $10,000 fine, and license suspension for 180 days to 2 years
Defenses to Marijuana DWI
To convict you of driving while intoxicated, the prosecution must prove that you were driving a motor vehicle and that you did not have the normal use of your physical or mental abilities. The state may introduce testimony from law enforcement about signs of impairment such as slowed reaction time and confusion and performance on standard field sobriety tests. The state may also introduce the results of a positive drug screen.
Field sobriety testing is not always accurate. If you are elderly, have medical conditions that cause physical impairment or lack of coordination, or if you have a condition that could cause natural nystagmus in your eyes, you may show signs of impairment according to a standard field sobriety test even if you were not under the influence of drugs or alcohol. Red eyes are one of the clues police look for when they suspect a person is under the influence of marijuana, but this can also be caused by fatigue. Driving while fatigued can also mimic signs of impairment and can affect a person's ability to pass a field sobriety test.
Likewise, drug tests are not always accurate. A drug test may show a positive result for marijuana even if you had ingested marijuana several days prior, and the accuracy of these tests can be attacked to raise a reasonable doubt about your guilt.
Other ways to attack a marijuana DWI charge include the following:
- The prosecution cannot prove that you were driving a motor vehicle
- Law enforcement did not have a valid reason to pull you over
- Law enforcement failed to administer standard field sobriety tests properly or did not have proper training to do so
- You did not give valid consent for a blood or urine sample
- Failure to store, transport or label a blood or urine sample in accordance with strict protocol
Marijuana has been legalized in other states for both medical and recreational use. Medical marijuana use in Texas is very limited to prescriptions for epilepsy patients to use a form of marijuana with high levels of CBD and low levels of THC. If you are caught driving while under the influence of marijuana in Texas, you can be convicted of a DWI even if you have a valid prescription for medical marijuana from another state.