Texas Marijuana DWI Laws: What You Need to Know in 2026

Marijuana & THC Laws in Texas

Texas maintains some of the strictest marijuana laws in the nation, though recent changes have created confusion about what’s legal and what’s not.

Current Texas Marijuana Laws

Possession of marijuana remains largely illegal in Texas, with limited exceptions. Here’s what you need to know:

• Criminal penalties apply for possession of any amount over 2 ounces
• Class B misdemeanor charges for possession under 2 ounces (up to 180 days in jail, $2,000 fine)
• Hemp-derived CBD products with less than 0.3% THC are legal
• Medical marijuana is extremely limited (low-THC cannabis for specific conditions only)

The Texas Compassionate Use Program

Texas allows limited medical marijuana use through the Compassionate Use Program. This program permits low-THC cannabis (up to 1 gram THC per package, effective September 2025) for patients with:

• Epilepsy and seizure disorders
• Multiple sclerosis
• ALS (amyotrophic lateral sclerosis)
• Autism
• Terminal cancer
• PTSD (for qualifying patients)
• Incurable neurodegenerative diseases
• Beginning September 1, 2025: Chronic pain, traumatic brain injury, Crohn’s disease, and terminal illnesses

However, legal medical marijuana use doesn’t protect you from DWI charges. Law enforcement can still arrest you for driving while impaired, regardless of whether your marijuana use was legally authorized.

Federal vs. State Law Conflicts

Marijuana remains federally illegal, creating complex legal situations. This federal-state conflict affects DWI enforcement because:

• Federal agencies can still prosecute marijuana cases
• Commercial drivers face federal penalties
• Professional licenses may be at risk
• Background checks will show marijuana-related arrests

What Is a Marijuana/THC DWI in Texas?

Under Texas Penal Code Section 49.04, you can be charged with DWI if you’re intoxicated while operating a motor vehicle. For marijuana cases, intoxication means:

1. Not having the normal use of mental or physical faculties due to marijuana consumption
2. Having a detectable amount of THC or its metabolites in your system

How Marijuana Leads to DWI Charges

Unlike alcohol DWI cases with clear BAC limits, marijuana DWI cases rely heavily on officer observations and field sobriety test performance. Common scenarios include:

Traffic Stop Indicators:

• Erratic driving patterns
• Slow reaction times
• Following too closely
• Weaving between lanes
• Driving significantly under the speed limit

Physical Observations:

• Red or bloodshot eyes
• Dilated pupils
• Strong odor of marijuana
• Slow or delayed speech
• Poor coordination

Real Case Result: In Dallas County case M13-39484, a possession of marijuana charge was dismissed through challenging the traffic stop’s validity.

Key Differences from Alcohol DWI

Marijuana DWI cases present unique challenges compared to traditional alcohol cases:

Legal Use vs. Alleged Impairment

The most confusing aspect of marijuana DWI law is understanding when legal use can still result in criminal charges. This distinction is crucial for your defense.

Medical Marijuana Use

Even if you’re a registered patient in the Texas Compassionate Use Program, you can still face DWI charges if an officer believes marijuana has impaired your driving ability.

Key considerations for medical users:

• Prescription doesn’t equal immunity from DWI prosecution
• Therapeutic levels can still cause impairment in some individuals
• Documentation of medical use can be helpful for your defense
• Timing of medication matters for impairment claims

Recreational Marijuana Context

While recreational marijuana remains illegal in Texas, many drivers consume marijuana legally in other states or use hemp-derived products. This creates complex legal situations when:

• You consumed marijuana legally in Colorado, California, or other legal states
• You’re using legal CBD products that may contain trace amounts of THC
• You have a medical marijuana card from another state
• You consumed marijuana days or weeks before driving

When Legal Use Still Leads to a DWI Stop

Zero-tolerance enforcement means that any detectable marijuana use can lead to DWI charges, regardless of when or where you consumed it.

Common scenarios:

• Residual THC from days-old use showing up in blood tests
• Cross-contamination from being around marijuana smoke
• False positive tests from legal CBD products
• Medical marijuana patients driving hours after consumption

📞 Call (972) 528-0116 to speak with an experienced Dallas DWI lawyer about your defense options.

Understanding Impairment vs. Intoxication

Texas law distinguishes between marijuana presence in your system and actual impairment of your driving ability. Presence doesn’t equal impairment because:

• THC metabolites remain detectable long after impairment ends
• Individual tolerance levels vary significantly
• Medical users may function normally with THC in their system
• Blood tests can’t determine when marijuana was consumed

Common Tests for THC Impairment

Unlike alcohol cases with standardized breath tests, marijuana DWI cases rely on less reliable testing methods. Understanding these tests is vital for building your defense.

Field Sobriety Tests

Standard field sobriety tests were designed for alcohol impairment detection and are significantly less accurate for marijuana impairment:

Horizontal Gaze Nystagmus (HGN):

• Limited effectiveness for marijuana detection
• Can be affected by medical conditions, medications, fatigue
• We challenge improper administration and environmental factors

Walk-and-Turn Test:

• Measures divided attention and balance
• Many factors affect performance: anxiety, medical conditions, footwear, road conditions
• Marijuana’s effects vary significantly between individuals

One-Leg Stand Test:

• Tests balance and concentration
• Poor performance can result from: nervousness, physical limitations, weather conditions
• Not scientifically validated for marijuana impairment

Drug Recognition Expert (DRE) Evaluations

Some Texas jurisdictions use specially trained Drug Recognition Experts to evaluate suspected marijuana impairment. DRE evaluations include:

12-Step Process:

1. Breath alcohol test
2. Interview with arresting officer
3. Preliminary examination
4. Eye examinations
5. Divided attention psychophysical tests
6. Vital signs examination
7. Dark room examinations
8. Examination for muscle rigidity
9. Examination for injection sites
10. Subject’s statements
11. Analysis and opinions
12. Toxicological examination

DRE Evaluation Challenges:

• Subjective interpretations by the evaluating officer
• Limited scientific backing for marijuana-specific conclusions
• Training varies significantly between officers
• Can be challenged through expert testimony

Blood and Urine Testing

Blood tests are the most common method for detecting THC in DWI cases, though they present several defense opportunities:

Blood Test Issues:

• Chain of custody problems from collection to analysis
• Improper storage can affect results
• Lab contamination or processing errors
• Warrantless blood draws may violate constitutional rights

THC Detection Windows:

Case Result: In Tarrant County case 1304698, a possession of controlled substance charge was dismissed due to improper blood sample handling and storage procedures.

No Marijuana Breathalyzer in Texas

Currently, no reliable breath test exists for marijuana impairment in Texas law enforcement. This creates both challenges and opportunities:

For Prosecution:

• Must rely on blood tests (more invasive)
• Longer processing times for results
• Higher costs and complexity

For Defense:

• More opportunities to challenge collection procedures
• Constitutional challenges to warrantless blood draws
• Time delays can benefit defense preparation

Penalties for Marijuana/THC DWI in Texas

Marijuana DWI penalties in Texas are identical to alcohol DWI penalties, but additional drug charges can significantly increase consequences.

First-Time Marijuana DWI

Class B Misdemeanor penalties include:

• Up to 180 days in jail
• Fines up to $2,000
• Driver’s license suspension for 90 days to 1 year
• DWI education program completion required
• Community service (24-100 hours)
• Probation instead of jail time (typically)

Second Marijuana DWI

Class A Misdemeanor with enhanced penalties:

• Up to 1 year in jail
• Fines up to $4,000
• License suspension for 180 days to 2 years
• Ignition interlock device installation required
• Mandatory minimum jail time may apply

Third or Subsequent DWI

Third-degree felony charges include:

• 2 to 10 years in prison
• Fines up to $10,000
• Driver’s license suspension up to 2 years
• Permanent criminal record
• Professional license consequences

Additional Marijuana Charges

Separate marijuana possession charges can accompany your DWI:

Possession Under 2 Ounces:

• Class B misdemeanor
• Up to 180 days jail
• Up to $2,000 fine

Possession 2-4 Ounces:

• Class A misdemeanor
• Up to 1 year jail
• Up to $4,000 fine

Commercial License Holders

Commercial drivers face severe consequences for marijuana DWI convictions:

• One-year CDL suspension for first offense
• Lifetime CDL revocation for second offense
• Federal regulations apply regardless of state law
• Career-ending implications for professional drivers

Long-Term Consequences

A marijuana DWI conviction creates lasting problems:

Employment Impact:

• Background checks reveal criminal record
• Professional licenses may be suspended or revoked
• Security clearances can be denied
• Transportation jobs become unavailable

Financial Consequences:

• Insurance rates increase significantly
• Court costs and attorney fees
• Lost wages from jail time or job loss
• Ignition interlock device costs

Personal Effects:

• Difficulty obtaining housing
• Student loan eligibility problems
• Immigration status complications
• Social stigma and family stress

🛡️ Don’t let a marijuana DWI conviction destroy your future. Call (972) 528-0116 for a confidential consultation.

Defense Options in Marijuana DWI Cases

Effective marijuana DWI defense requires understanding both the science and law behind THC impairment claims. Our legal team uses proven strategies to challenge prosecution evidence.

Challenging Probable Cause

Every DWI case begins with the traffic stop, and we scrutinize whether officers had legitimate reasons to pull you over:

Common Probable Cause Challenges:

• Pretextual stops using minor traffic violations to investigate DWI
• Insufficient evidence of actual traffic law violations
• Officer bias or profiling in marijuana cases
• Anonymous tips without corroborating evidence

Case Result: In Dallas County case M13-65512, an unlawful weapons carrying charge was dismissed by proving the initial traffic stop lacked probable cause.

Contesting Field Sobriety Test Validity

Standard field sobriety tests are unreliable for marijuana impairment detection, providing multiple defense opportunities:

Test Administration Issues:

• Improper instructions given to the driver
• Environmental factors affecting performance (lighting, weather, road conditions)
• Officer training deficiencies in marijuana-specific indicators
• Medical conditions explaining poor test performance

Scientific Challenges:

• No validation studies for marijuana-specific impairment
• Individual variation in marijuana effects
• Anxiety and nervousness from police interaction affecting results
• Physical limitations unrelated to impairment

Blood Test Chain of Custody Issues

Blood evidence must be properly collected, stored, and tested to be admissible in court. We investigate every step:

Collection Problems:

• Unqualified personnel drawing blood samples
• Improper sterilization procedures
• Missing consent or warrant requirements
• Constitutional violations in forced blood draws

Storage and Transport:

• Temperature control failures affecting sample integrity
• Delayed testing allowing sample degradation
• Lost or contaminated samples
• Chain of custody gaps in documentation

Laboratory Analysis:

• Equipment calibration errors
• Technician qualifications and training
• Quality control failures
• Cross-contamination between samples

Expert Testimony Strategies

Scientific evidence requires scientific challenges. We work with qualified experts to contest prosecution claims:

Toxicology Experts:

• Challenge THC blood level interpretations
• Explain individual tolerance variations
• Demonstrate testing limitations
• Provide alternative explanations for test results

Medical Experts:

• Explain medical conditions affecting field sobriety tests
• Discuss prescription medication interactions
• Address chronic pain or mobility issues
• Challenge impairment conclusions

Negotiation Strategies

Not every case goes to trial. Experienced negotiation can achieve favorable outcomes:

Charge Reduction Options:

• Reckless driving instead of DWI
• Obstruction of highway plea agreements
• Deferred adjudication avoiding conviction
• Probation instead of jail time

Case Results: Multiple cases have resulted in reductions from DWI to obstruction of highway, including Dallas County case M13-12711.

Constitutional Challenges

Your constitutional rights don’t disappear during a DWI investigation:

Fourth Amendment Violations:

• Unreasonable searches and seizures
• Warrantless blood draws without exigent circumstances
• Extended detentions without probable cause
• Vehicle searches exceeding legal scope

Fifth Amendment Protections:

• Right to remain silent
• Protection against self-incrimination
• Miranda rights violations
• Coerced confessions

🔍 Learn more about our drug-related DWI defense approach.

Why You Need a Texas DWI Lawyer

Marijuana DWI cases involve complex legal and scientific issues that require specialized knowledge and experience. Attempting to handle your case without qualified representation puts your future at risk.

Texas-Specific Legal Nuances

Texas DWI law has unique aspects that out-of-state attorneys may not understand:

• Texas Transportation Code specific requirements
• Local prosecutor practices in different counties
• Judge preferences and sentencing patterns
• Administrative license revocation procedures
• Texas-specific plea bargain opportunities

Our Track Record of Success

The Law Offices of Richard C. McConathy has successfully defended marijuana DWI cases throughout North Texas:

Recent Results:

• DWI Dismissed (Dallas County M13-39484) – Possession of Marijuana charge dismissed
• DWI Dismissed (Tarrant County 1304698) – Possession of Controlled Substance charge dismissed
• DWI Reduced (Dallas County M13-11040) – Possession of Marijuana reduced to Class C Drug Paraphernalia

Our Experience Includes:

• 35+ years of criminal defense experience
• 1000+ cases dismissed in the DFW area
• 6000+ criminal cases handled
• Serving 16+ counties in North Texas

Local Court Knowledge

Different Texas counties handle marijuana DWI cases differently. Our experience in local courts provides advantages:

• Dallas County: Known for aggressive DWI prosecution but open to negotiation with strong defense
  
  
• Tarrant County: More conservative approach with emphasis on treatment programs
  
  
• Collin County: Tech-savvy prosecution requiring sophisticated defense strategies
  
  
• Denton County: Growing caseloads creating plea bargain opportunities

Protecting Your Professional Future

A DWI conviction affects more than criminal penalties:

• Professional licenses in healthcare, education, finance, and law
• Security clearances for government and military work
• Commercial driving privileges and transportation careers
• Immigration status for non-citizens

We understand these collateral consequences and work to minimize their impact through strategic defense planning.

⚖️ Contact us at (972) 528-0116 for a confidential consultation.

Frequently Asked Questions

Can I get a DWI for marijuana if I legally use it?

Yes, you can still be charged with DWI even if your marijuana use was legal under Texas medical marijuana laws or if you consumed marijuana legally in another state. Legal use doesn’t provide immunity from DWI charges if an officer believes marijuana has impaired your driving ability.

Do field sobriety tests work for marijuana?

Field sobriety tests are significantly less reliable for detecting marijuana impairment compared to alcohol. These tests were designed for alcohol detection and have not been scientifically validated for marijuana-specific impairment. Many factors unrelated to marijuana use can cause poor performance on these tests.

What if my THC blood test was low?

Low THC blood levels can still result in DWI charges in Texas because there’s no specific legal limit for THC like there is for alcohol. However, low levels help your defense by making it harder for prosecutors to prove impairment. We can challenge whether such low levels could have actually impaired your driving ability.

How long does THC stay in your system?

THC detection windows vary significantly based on usage patterns and individual factors:

• Blood: Active THC typically 3-4 hours, metabolites up to 30 days
• Urine: Up to 30 days for regular users
• The key issue: Detectable doesn’t mean impaired. THC can be detected long after any impairing effects have ended.

Will a marijuana DWI go on my record?

A DWI conviction becomes part of your permanent criminal record and cannot be expunged in Texas. However, we may be able to get your case dismissed or reduced to a lesser charge that can be expunged. This is why immediate legal representation is crucial for protecting your future.

Can I refuse a blood test for marijuana DWI?

You can refuse a blood test, but Texas has implied consent laws meaning refusal can result in automatic license suspension. Additionally, officers can obtain a warrant for forced blood draws. The decision to refuse should be made carefully with legal advice, as refusal doesn’t prevent prosecution and may have additional consequences.

What’s the difference between DWI and drug possession charges?

DWI focuses on impaired driving, while possession charges relate to having marijuana in your control. You can face both charges simultaneously, significantly increasing potential penalties. Each charge requires a separate defense strategy, and conviction on either can have serious consequences.

How much does a marijuana DWI lawyer cost?

Legal fees vary based on case complexity, but the cost of experienced representation is significantly less than the long-term consequences of a DWI conviction. We offer payment plans and financing options to make quality defense accessible. The investment in proper legal representation often saves money by avoiding conviction consequences like increased insurance rates, job loss, and professional license issues.