THC DEFENSE
San Antonio THC Possession Lawyer
THC vape, concentrate, oil, wax, gummy, and hemp-product cases can involve legal and laboratory issues that differ from ordinary marijuana possession. A careful defense starts with the substance, the testing, and whether the State can actually prove what it claims.
THC CASES
Common THC Cases
Vape Cartridges
Cases involving cartridges often turn on residue, packaging, ownership, and whether the item was actually tested.
Wax and Concentrates
Concentrate allegations can carry different weight and often depend on lab methods and how the material was collected.
THC Gummies
Edible cases may involve labeling, dosage assumptions, and questions about what the product really contained.
THC Oils
Oil-based products can raise chain-of-custody and identification issues, especially when containers are shared or unmarked.
Hemp Products
Hemp-derived products can create confusion because appearance and odor do not reliably prove unlawful THC content.
Constructive Possession
When multiple people had access to a vehicle, room, or container, possession still has to be tied to a specific person.
EVIDENCE
A THC Vape Is Not Self-Proving Evidence
A cartridge, pen, gummy package, jar of wax, or bottle of oil does not prove its own contents. Packaging, branding, appearance, flavor names, and online product descriptions do not by themselves establish what substance was actually seized or the THC concentration, if any, in that item. A product may be marketed online as containing THC and still require testing of the actual seized device before the State can establish what that particular cartridge contained.
The State still has to identify what item was tested, connect that item to a particular person, and show what the testing actually established. In many cases, that requires more than an officer’s conclusion, a product label, or a field-level assumption.
The accusation is not the proof. The evidence still has to hold up.
Castanon Law Firm
That is why THC cases often require close attention to seizure details, photographs, packaging, evidence handling, chain of custody, and the actual testing record rather than broad assumptions based on appearance alone.
LABORATORY
The Lab Test Matters
In a THC possession case, the laboratory result can be central, but the actual method matters. A defense may examine what item was tested, whether the method was used to identify a substance, whether it attempted to quantify THC concentration, how the sample was selected, and how the report describes the result.
A defense may also examine whether the sample was properly preserved, whether the chain of custody is complete, whether the tested sample matches the seized item described by officers, whether the testing answered the legal question at issue, and whether the report leaves room for challenge.
LEGAL ISSUES
Hemp, Marijuana, and THC
Texas law does not treat every cannabis-derived product the same. Hemp is legally defined as cannabis and its derivatives containing no more than 0.3% delta-9 THC on a dry-weight basis. Products that meet that definition are excluded from the Texas Controlled Substances Act’s definition of a controlled substance.
That means a vape, gummy, oil, wax, or other processed product is not automatically illegal simply because it contains cannabinoids or is marketed as a THC product. The legal question can depend on what cannabinoids are present, the concentration of delta-9 THC, and whether the actual seized product falls within Texas’s statutory definition of hemp.
Hemp Distinctions
A product qualifies as hemp based on its actual chemical composition, not merely because the package says “hemp,” “legal,” or “Farm Bill compliant.” If the product contains no more than 0.3% delta-9 THC on a dry-weight basis and otherwise falls within the statutory definition, it may qualify as hemp under Texas law. See Texas Hemp Law
What Makes a Product Legal
Texas law defines hemp in part by a Delta-9 THC concentration of no more than 0.3% on a dry-weight basis, but that threshold does not make every cannabinoid product lawful. The cannabinoid involved, how it was produced, the concentration found in the actual product, and current Texas controlled-substance scheduling may all matter. Delta-8 THC is currently treated by Texas DSHS as a controlled substance except for naturally occurring trace amounts. See Consumable Hemp Program
What Can Make a Product Illegal
If the actual product does not meet the statutory definition of hemp—for example, because its delta-9 THC concentration exceeds 0.3% on a dry-weight basis—the hemp exclusion may no longer apply. At that point, the State may attempt to treat the substance as marijuana or a controlled THC substance depending on the product and the evidence. THC is generally classified in Penalty Group 2 under Texas law. See Texas Controlled Substance Act 481.103
Delta-8 THC in Texas
Delta-8 THC is currently treated as a controlled substance in Texas. In 2026, the Texas Supreme Court upheld the Department of State Health Services’ authority to classify Delta-8 THC as a controlled substance. DSHS subsequently reinstated its scheduling clarification effective July 31, 2026.
Under the current DSHS position, only naturally occurring trace amounts of Delta-8 THC in the hemp plant from which a consumable hemp product was manufactured are exempt. Products labeled as containing Delta-8 THC, or shown to contain more than trace amounts of Delta-8 THC, may be treated as controlled-substance products and referred to law enforcement.
This makes the actual laboratory evidence especially important. A package labeled “hemp,” a retail purchase, or a Delta-9 THC concentration below 0.3% does not necessarily establish that a product containing Delta-8 THC is lawful under current Texas law.
Why the Lab Result Matters
A label or website description cannot answer that question by itself. The defense should examine whether the seized item was actually tested, what laboratory method was used, whether the test merely detected THC or actually measured the relevant concentration, and whether the tested sample can be tied to the item attributed to the defendant.
DEFENSE THEMES
Possession Still Has to Be Proven
Knowledge and Control
The State must do more than show an item existed. It still has to prove a person knew about it, exercised care, custody, control, or management over it, and was not merely near it.
Shared Spaces
If the item was found in a shared vehicle, bag, room, or residence, the defense can examine whether the evidence really points to one person or instead raises a constructive-possession issue.
Circumstantial Gaps
Weak links in location, ownership, statements, body-camera evidence, or evidence handling can matter when the prosecution tries to prove possession beyond a reasonable doubt.
SEARCH ISSUES
Search and Suppression Issues
Some THC cases begin with a traffic stop, a detention, a vehicle search, a consent issue, questioning, or a claim that an officer smelled marijuana. Whether the stop, continued detention, search, consent, and questioning were lawful can be as important as the substance allegation itself.
A defense may review the basis for the stop, the reason for any continued detention, the scope of the search, body-camera footage, the timing and wording of any consent, and statements attributed to the accused.
If the search was unlawful, the evidence may be subject to challenge.
Castanon Law Firm
Suppression issues can change the direction of a case, especially when the prosecution depends heavily on what officers found, what was said on body-camera video, or what officers claim was admitted during a stop or search.
STRATEGY
How a THC Possession Case Can Be Defended
Every case depends on its facts, but a defense may focus on the legality of the stop and detention, the search and consent issues, what item was actually seized, the testing method used, the chain of custody, the identity or concentration findings reported by the lab, and whether possession can actually be proven.
Challenge the stop, detention, or search
Examine the method and report
Test constructive possession claims
Review body-camera and statements
Facing a THC Charge in San Antonio?
THC possession cases can involve laboratory, possession, and search issues that are more specific than a simple label on a package or an officer’s assumption about what an item contained.
Castanon Law Firm represents clients facing criminal charges in San Antonio and throughout Bexar County.