Texas Traffic Stops: Your Rights, Hemp Laws and the Constitution

By Tad Nelson – Board Certified Criminal Defense Lawyer

What to Know About Hemp Laws

• In Texas as of 2026, officers still routinely claim the odor of marijuana as probable cause to search vehicles during a traffic stop, even though hemp became legal under the 2019 Texas Hemp Farming Act.
• Legal hemp plant material and illegal marijuana smell identical because the same terpenes produce their odor-neither police nor K9s can tell them apart by smell-but appellate courts still allow “odor alone” to justify a vehicle search.
• During a traffic stop in Galveston, Houston, or surrounding counties, stay calm, keep hands visible, provide required documents, refuse consent to search if you choose, and never argue your case on the roadside.
• If you are arrested after a stop involving alleged cannabis odor, hemp-based products, or THC drinks, contact Tad Nelson & Associates immediately to challenge the stop, the search, and the forensic evidence.

Introduction: Why Traffic Stops Matter in Modern Texas

A routine traffic stop on I-45 through Galveston County or a lane-change citation on TX-3 near League City can escalate into a DWI, drug possession, or weapons case in a matter of minutes. Across Harris and Galveston County, a significant number of serious criminal cases begin with nothing more than an alleged minor traffic violation-speeding, a broken taillight on Broadway in Galveston, or a wide turn off the Gulf Freeway.

Since the 2019 Texas Hemp Farming Act legalized the hemp plant and its derivatives, the line between legal hemp and illegal marijuana has become scientifically blurry. Yet the law on probable cause during car stops has not kept pace with that change. At Tad Nelson & Associates, our defense practice is led by an ACS Forensic Lawyer-Scientist with a Master’s degree in Forensic Toxicology-a unique combination we use to attack weak stop and search justifications at every stage of a case. This article walks you through what to do during a traffic stop, how hemp laws and THC products affect probable cause, and when to fight a search or arrest in court.

What To Do The Moment You See Police Lights

Seeing red-and-blue lights in your rearview mirror triggers anxiety for almost every driver. Channel that energy into following these steps:

• The officer must activate emergency lights to signal you to pull over safely. When you see them, slow down gradually-don’t slam the brakes-signal right, and pull onto the shoulder or the nearest safe side street. Exiting onto a well-lit gas station lot is perfectly acceptable.
• Drivers must pull over safely when signaled by police. Turn off the engine, turn on interior lights during a nighttime traffic stop, lower the window partway, turn off the radio, and place both hands on the steering wheel.
• Keep hands visible on the steering wheel at all times. Sudden movements or reaching under seats heighten officer suspicion and perceived safety risks.
• Keep passengers calm with hands in plain sight. Instruct them not to reach for anything.
• You must show your driver’s license upon request, along with registration and proof of insurance. Have those accessible, but avoid digging around the glove box or console until the officer approaches and asks you to display them. Showing these documents calmly sets the right tone.

Understanding the Legal Basis for a Texas Traffic Stop

The Fourth Amendment protects you against unreasonable searches and seizures-and that protection follows you into your vehicle. A traffic stop typically follows a structured legal and procedural framework, and understanding that framework is the first step toward protecting yourself.

• Common justifications for a stop: alleged traffic violations (speeding, failing to signal, expired tags), equipment violations (broken headlight), or reasonable suspicion of DWI or drug activity.
• Reasonable suspicion requires specific, articulable facts suggesting criminal activity-not just a hunch. For example, weaving within a lane on the Gulf Freeway might be cited as DWI suspicion, but the basis must be more than a gut feeling.
• Probable cause is a higher standard, required to arrest or to search a vehicle without a warrant under the automobile exception. If an officer believes they have probable cause, they can expand the scope of the traffic stop.
• A typical traffic stop includes phases of initiation, identification, information checks, and resolution. A traffic stop may conclude with a warning, a citation, or further investigation based on reasonable suspicion-but officers often stretch minor infractions into fishing expeditions for drugs, guns, or intoxication evidence. That is where an experienced criminal defense attorney can directly challenge the stop later.

Your Rights During a Traffic Stop in Texas

Texans do not surrender their constitutional rights when they are pulled over. But they can easily make things worse by arguing or refusing basic lawful orders. Your rights must be asserted calmly and respectfully during a traffic stop-never on the roadside through confrontation.

• Right to remain silent. During a traffic stop, you have the constitutional right to remain silent. Refusing to answer investigative questions is your right. You are not required to answer questions beyond providing documents, so you can politely decline to respond to “Where are you coming from?” or “Have you been smoking?”
• Identification requirements. Drivers must present a license and registration upon request. Passengers may be asked for identification but are not required to provide it absent reasonable suspicion or arrest.
• Exiting the vehicle. Officers can order passengers out of the vehicle at any time for safety reasons under U.S. Supreme Court precedent. You can be ordered out of your vehicle during a traffic stop. Refusing to comply with lawful requests can lead to arrest.
• Refusing consent to search. You can refuse to consent to a vehicle search during a traffic stop. Use clear language: “Officer, I do not consent to any searches.” An officer must have probable cause, a warrant, or consent to search your car-but even if you refuse, they may search if they claim independent probable cause. That decision can be challenged later in court. Legal challenges to a stop should be pursued after the encounter, not on the roadside.
• You can ask if you are free to go during a traffic stop. If the answer is yes, leave calmly.

How Hemp, Marijuana, and THC Drinks Complicate Traffic Stops

The 2019 Texas Hemp Farming Act (HB 1325) legalized hemp-defined as Cannabis sativa L. with a delta-9 THC concentration of 0.3% or less by dry weight. The state removed hemp from the statutory definition of “marihuana,” and a growing industry of hemp companies now sells everything from flower to edibles to textiles made from the plant.

The problem is scientific: the odor-producing terpenes-myrcene, pinene, caryophyllene-are identical in legal hemp and illegal marijuana. It is difficult for an officer or a drug dog to distinguish them by smell alone. Drivers legally carrying hemp based products such as CBD flower, hemp vapes, or compliant THC drinks purchased in Houston may still face a roadside search because officers “smell weed.”

Open containers of THC drinks or spilled hemp flower in a car can lead officers to suspect illegal marijuana or DWI with drugs, even when the products comply with government regulations. Lab testing using technologies like HPLC is required to verify and measure total THC content above 0.3% at trial-but on the roadside, officers rely on odor, appearance, and packaging. The rise of these products means a driver leaving a Galveston smoke shop with labeled hemp products can still be stopped on Seawall Boulevard and searched on the basis of smell alone.

Has “Plain Smell” Probable Cause Changed Since Hemp Became Legal?

Under current Texas appellate case law, the odor of cannabis still generally gives officers probable cause to search a vehicle-despite the effect of HB 1325 making hemp legal. The core question of whether probable cause has changed since hemp legalization has been answered by intermediate courts: it has not.

The leading case is State v. Gonzales, decided by the Dallas Court of Appeals in the year 2023. In December 2021, two officers in parked patrol cars smelled a strong odor of marijuana from a passing pickup, followed it to a gas station, smelled it again, and searched the truck, finding plant material and a firearm. The trial court suppressed the evidence, but the appellate court reversed, holding that odor alone still created probable cause under the automobile exception. Critically, the officers admitted they could not tell hemp from marijuana by smell.

Intermediate appellate courts across Texas-in decisions like Cortez v. State (Dallas, 2022), Isaac v. State (San Antonio, 2023), and Outlaw v. State (Corpus Christi-Edinburg, 2025)-agree. Their reasoning: probable cause requires only a “fair probability” that contraband will be found. Because marijuana possession remains illegal and prevalent, the smell meets that threshold. Courts have ruled that a legal, innocent explanation does not destroy probable cause, because law enforcement is not required to rule out all innocent explanations before allowing a search.

From a forensic toxicology standpoint, this result is deeply frustrating. There is no way to perform a quantification of THC concentration by smell. A Baylor University law review study has highlighted the “forensic crisis” this creates for prosecution and defense alike. The defense community is pushing for an “odor plus” standard-odor combined with impairment, admissions, or missing hemp packaging-but as of 2026, appellate courts have not adopted that rule statewide. Eventually, the Texas Court of Criminal Appeals may have to resolve this tension.

From Traffic Stop to DWI or Drug Charge: How Cases Escalate

A minor stop in Galveston or Harris County can snowball quickly into serious charges: DWI/DUI, possession of marijuana, felony THC concentrate, unlawful carry of a weapon, or child endangerment. Here is how it typically happens:

1. Officer claims to smell marijuana, asks the driver to exit, and conducts field sobriety tests. A search of the car turns up hemp based products, THC drinks, or prescription medications.
2. Officers use “I smell marijuana” as the purpose for prolonging the stop beyond the time needed to issue a warning or ticket, then call in a K9 unit or conduct a more invasive search. (The TCCA’s November 2025 Organ decision did limit K9 intrusions through open vehicle windows-a response to overreach.)
3. Alleged signs of impairment-bloodshot eyes, “odor of alcohol,” slow movements-get layered on top of cannabis odor to support DWI or drugged driving accusations.

At Tad Nelson & Associates, we focus on dissecting each step-from the initial lane violation through the search and the arrest-looking for timing issues, lack of reasonable suspicion, pretext, or inconsistent officer testimony.

How Tad Nelson & Associates Attack Odor-Based Searches

Tad Nelson holds the ACS-CHAL Forensic Lawyer-Scientist designation and a Master’s degree in Forensic Toxicology. That background is not decorative-it shapes how we challenge every search that begins with “I smelled marijuana.”

• Suppression hearings: We challenge whether the officer truly had reasonable suspicion for the stop, whether the stop was improperly prolonged, and whether odor alone was enough under the specific fact pattern. Trial judges in the 1st and 14th Court of Appeals districts are bound by current appellate precedent, but we preserve the issue for the Court of Criminal Appeals on every case-building the record for the change in law that science demands.
• Trial cross-examination: We force officers to admit under oath that they smelled terpenes, not THC. They cannot tell the difference between a 0.3% hemp plant and a 15% marijuana plant by nose. That admission, supported by expert testimony, can undermine the officer’s performance on the stand and build reasonable doubt.
• Lab analysis challenges: We examine HPD and DPS toxicology reports, challenge field tests that cannot quantify THC, and demand that the prosecution produce HPLC results showing THC content above the legal range. Without that processing of lab evidence, convictions should not stand. We work to get evidence excluded when the science does not support the charge.

Special Issues: Hemp-Based Products, THC Drinks, and Vehicle Searches

Traffic stops increasingly involve modern cannabinoid products-not just traditional marijuana flower. Texas drivers now carry a wide range of items: CBD or hemp flower, Delta-8 and Delta-9 hemp edibles, THC drinks bought from local shops, vape cartridges, and tinctures labeled as hemp based products.

• Packaging matters. Certificates of Analysis (COAs), QR codes, and labels showing “hemp compliant 0.3% Δ9 THC or less” can help document legality. Loose or repackaged products make it easier for officers to claim they suspected illegal marijuana.
• THC drinks and open containers. Prosecutors may try to analogize these products to alcohol, particularly in DWI investigations. A November 2024 vape ban (SB 2024) made cannabinoid vape sales a Class A misdemeanor, adding another layer of interest for law enforcement.
• Field tests cannot measure THC. Colorimetric kits and officer observation are not reliable technologies for measuring total THC as required by Texas law. Only quantitative lab methods can comply with evidentiary standards. Drivers who regularly transport hemp products near Galveston or Houston should keep purchase receipts, original packaging, and digital COAs easily accessible-while understanding that an officer may still decide to search.

Protecting Yourself After a Questionable Traffic Stop

The most important decisions often happen after the stop: what you say, what you sign, and how quickly you contact a lawyer.

• Do not discuss the facts of the stop with anyone but your attorney-not with friends, not on social media, and not in text messages that can be subpoenaed. Avoid sharing details that could be used against you.
• You can document a traffic stop by noting details immediately afterward, such as officer information, location, time, what the officer said, references to odor, whether you gave consent to search, whether a K9 was used, and names of passengers.
• Dashcam, bodycam, and nearby business surveillance footage are critical. Our firm sends preservation letters and discovery requests promptly to track and access that evidence before it disappears.
• If you are in Galveston County, Harris County, Brazoria County, or nearby areas, schedule a free consultation with us as soon as you receive a citation or are arrested.

How Google Search, Reviews, and Online Research Affect Your Legal Choices

Most people first turn to a Google search right after a traffic stop or arrest, often from their phone in the car. While articles on various pages and urls across the web can provide general guidance, Texas traffic stop law is fact-sensitive and changes with new appellate decisions. Generic content from other states-or queries that lead to outdated information-can be misleading. Search engines like Google crawl and index thousands of pages, but not every site provides accurate, current Texas-specific advice.

Look beyond star ratings and ads when choosing a lawyer. Check for real experience with traffic-stop-based DWI and drug cases, forensic toxicology training, and local trial history. Users searching for legal help should understand that our website content is designed to educate, but we customize strategy to each client’s circumstances. Nothing you read in a Google search result replaces confidential, one-on-one legal advice tailored to the exact facts of your stop and any hemp or THC products involved.

When to Call Tad Nelson & Associates After a Traffic Stop

Time is not on your side after a traffic stop leads to criminal charges. In many DWI cases, you have only 15 days from notice of suspension to request an Administrative License Revocation (ALR) hearing-making immediate contact with counsel critical.

Call us if:

• You were arrested after a traffic stop for DWI, drug possession, or any charge tied to alleged cannabis odor
• Hemp based products or THC drinks were seized from your vehicle
• You face possible license suspension or felony charges
• You believe your rights were violated during the stop or search

We offer free consultations to review dashcam and bodycam footage, offense reports, and lab reports-and to map out a defense strategy that may include motions to suppress the stop or search. If you are anywhere in Greater Houston, Galveston, League City, Texas City, or nearby communities, reach out before making any plea decisions.

Frequently Asked Questions About Texas Traffic Stops, Hemp, and THC

Can an officer search my car in Texas just because they say they smell marijuana?

Under current Texas appellate decisions like State v. Gonzales (2023), most courts still treat the odor of marijuana as sufficient probable cause to search a vehicle under the automobile exception. This remains the result even though legal hemp and illegal marijuana smell the same. Defense attorneys are actively challenging this rule and preserving the issue for higher court review. A search that seemed legal on the roadside can still be attacked later in court by a firm that understands forensic science and Fourth Amendment law.

Should I tell the officer that the cannabis smell is from legal hemp or THC drinks?

You are not required to explain smells or admit to using any product. If you choose to speak, avoid making incriminating statements about marijuana use or impairment. Calmly stating “Those are legal hemp products I purchased” may help in some scenarios but does not guarantee officers will forego a search. Anything said can be used later in court, so invoking the right to remain silent and asking for a lawyer is generally the safest choice once questioning turns to drugs or alcohol.

What if I refused consent to search but the officer searched my vehicle anyway?

Officers often claim independent probable cause-such as odor, visible contraband, or behavior-to search without consent. Clearly but calmly state your refusal: “I do not consent to any searches.” Do not interfere physically if the search proceeds. This creates a clean record for a later motion to suppress, where your attorney can challenge whether probable cause truly existed.

Can I record my traffic stop on my phone in Texas?

You can legally record police encounters as long as you do not interfere with their duties or officer safety. Position your phone safely mounted on the dash using an app or a holder, rather than reaching around in a way that could be misinterpreted as a threat. Bodycam and dashcam footage from the officer’s side will also be important evidence that your attorney can obtain during the case.

Are hemp gummies, vapes, or THC drinks I bought legally still risky to carry in my car?

Even lawfully purchased hemp-based products can raise suspicion during a traffic stop if officers confuse them with illegal marijuana or higher-THC items. Especially since the July 31st law changes. Nobody, including police officers, is sure what the law is right now. Keep products in original packaging with labels and QR codes, along with receipts or Certificates of Analysis, to help document legality. Despite these precautions, officers may still search or arrest, and contacting a defense lawyer promptly is crucial if products are seized or charges are filed.