By Evan Lange
Yes, Texas private employers can generally drug test job applicants and employees, and they can fire employees who test positive for illegal drugs. Under the ADA, a test for illegal drugs isn’t a medical exam, and current illegal drug use isn’t protected. But there are limits: employers generally can’t demand a list of all your lawful prescription medications, people in or who have completed recovery programs who no longer use drugs illegally are protected from discrimination, and testing can’t be applied selectively based on race, sex or another protected trait. For unemployment, the Texas Workforce Commission requires an employer to prove a positive test with a written policy, your consent, chain of custody and lab confirmation.
Pre-employment screens, random tests in safety-sensitive jobs, post-accident tests: drug testing is common across Houston’s energy, construction, transportation and healthcare industries. Most testing is legal. What matters is how it’s done and what happens next.
Workers in DOT-regulated jobs, like commercial truck drivers, have federal testing requirements on top of company policy.
Learn more in our disability discrimination guide and reasonable accommodations.
Marijuana remains illegal under Texas law except for limited low-THC medical use under the Texas Compassionate Use Program, and employers can generally still enforce drug-free workplace policies. Some CBD and hemp products can contain THC and cause a positive test, so check labels carefully if your job tests.
A positive test can be “misconduct” that disqualifies you from unemployment, but the Texas Workforce Commission requires the employer to prove it. TWC guidance says the employer generally needs:
TWC also says employers that fire based only on one initial screen will almost always lose if the employee denies drug use. See collecting unemployment if you were fired and termination for cause.
See retaliation in the workplace and, for lie detector tests, lie detector tests at work.
Generally yes. Texas private employers can drug test applicants and employees, including random testing under a written policy, as long as testing is not applied in a discriminatory or retaliatory way.
Usually yes, for illegal drug use. Current illegal drug use is not protected by the ADA. Lawful use of a prescribed medication is treated differently, and you should explain it to the employer or medical review officer.
Possibly. The Texas Workforce Commission requires the employer to prove a written policy, your consent, chain of custody, lab confirmation and a result above the cutoff. Employers relying only on an initial screen often lose.
Yes. People who no longer use drugs illegally and are in or have completed a rehabilitation program are protected from discrimination based on past addiction, though employers may test to confirm they are not using.
It can. Some CBD and hemp products contain THC, which may cause a positive result, and employers can generally enforce drug-free policies.
The Lange Firm represents employees in Houston and across Texas. Attorney Evan Lange can review your employer’s testing policy, the results and whether a firing was discrimination, retaliation or a wrongful termination.
A drug test is a process.
Your employer has to follow it fairly.
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