Workplace Drug Testing Laws in Missouri: What Employers Can Do

Federal law does not prohibit workplace drug testing but establishes baseline standards through the Department of Transportation (DOT) and Department of Labor (DOL). The Controlled Substances Act (21 U.S.C. § 801 et seq.) provides the legal framework for drug testing, while 49 U.S.C. § 102 mandates drug testing for transportation industry employees operating commercial vehicles. Federal regulations at 29 CFR Part 40 establish procedures for drug testing, including chain of custody requirements, certified laboratory standards, and confirmation testing protocols.

Employers in safety-sensitive positions (transportation, nuclear power, aviation) must comply with federal DOT regulations. The Americans with Disabilities Act (42 U.S.C. § 12101) limits testing for individuals in recovery or with past substance abuse histories. The Workplace Substance Abuse Testing Act of 1988 provided guidelines that most states, including Missouri, adopted as models. Federal law allows employers broad discretion to test applicants and employees but requires use of certified laboratories, proper chain of custody procedures, and notice to employees. The EEOC enforces federal standards and addresses discrimination claims related to drug testing policies. Remedies under federal law include injunctive relief, compensatory damages, and attorney fees for violations.

Missouri Revised Statutes § 285.017 governs workplace drug testing and is generally permissive toward employers, making Missouri law slightly weaker than some states that impose stricter notice or procedural requirements. However, § 285.017 does establish mandatory procedural protections that employers must follow.

Under Missouri law, employers may conduct drug tests on applicants and employees, but must provide "reasonable notice" before testing. The statute does not define "reasonable notice" with specific timeframes, leaving some ambiguity that courts have interpreted to mean notice sufficient to allow the employee to prepare (typically at least 24 hours unless testing is for cause after an incident). Pre-employment testing is permitted if the employer applies the same test to all applicants for the same position, ensuring non-discriminatory application.

Missouri law requires employers to use certified laboratories for drug testing and to follow established procedures for specimen collection and analysis. The state extends coverage to all employers regardless of size, though practical enforcement focuses on larger employers. Missouri Revised Statutes § 285.035 provides employee protections regarding test results: employees have the right to receive their test results, know the specific substance detected, and request confirmation testing at their own expense if they dispute results. If confirmation testing is requested, the original sample must be retained and tested by a different certified laboratory.

Missouri's law does not prohibit marijuana testing but does not provide special protections for off-duty cannabis use. Unlike some states, Missouri has not legalized recreational marijuana, so employers retain broad discretion to test for cannabis and take adverse action based on positive results. The state law is weaker than federal ADA standards in that it does not explicitly address testing individuals with known substance abuse histories. Missouri employers must still comply with federal DOT standards for transportation employees, which are stricter than state law. Remedies under Missouri law include civil liability for wrongful termination if an employer violates the statutory procedures, and employees may pursue state tort claims for negligent or intentional testing procedures.

Missouri law permits employers to refuse employment or terminate employees who test positive, provided the employer follows statutory procedures—this is not considered wrongful termination under state law if procedures are followed. At-will employment doctrine in Missouri (§ 290.260) means employers can terminate for positive drug tests absent a specific contract protecting the employee.

Safety-sensitive positions are an exception where employers have broader discretion: transportation employees, healthcare workers, and employees in federal safety programs (nuclear power, aviation) are subject to stricter federal DOT standards. These employers may conduct testing without the same notice requirements that apply to other positions, though they must still follow federal chain of custody and laboratory certification procedures.

Missouri law does not cover independent contractors—only employees are protected. Volunteer positions and unpaid internships fall outside the statute. Union employees may have greater protections through collective bargaining agreements that impose stricter notice or procedural requirements than state law, and employers must respect those agreements.

Employees with prior agreements to drug testing (signed acknowledgment forms) have limited recourse to challenge the testing itself, though they retain the right to dispute results. Refusal to submit to a lawfully conducted test is not protected conduct and may result in termination. Missouri does not require a medical reason exemption from testing, though the ADA may provide limited protections for employees with documented substance abuse disorders if they are in recovery and pose no safety risk.

Testing conducted outside certified laboratory procedures or without proper chain of custody is legally vulnerable, but employers retain the burden of proving compliance. Private employers (not subject to federal funding requirements) have broader discretion than public employers who must comply with state constitutional privacy protections under Missouri Constitution Article I, Section 15, which affords stronger privacy rights to public employees.

Step 1: Document Everything. From the moment you suspect a violation, keep detailed records: date and time of test notification, exact words of notice given, location of test, name of testing facility, names of witnesses, sample collection procedures observed, and any deviations from standard protocol. Request a copy of the chain of custody form and the laboratory report showing the specific substance detected. Photograph or retain documentation of the test facility's certification status. If you took the test, save any pre-test instructions or forms you signed. Create a timeline of events leading to the test (e.g., incident investigation, routine screening). Keep all communications with your employer about the test in writing if possible, or write a dated summary of oral conversations immediately after they occur.

Step 2: Internal Complaint Process and Notice Requirements. Before filing an external complaint, notify your employer in writing (email, certified mail, or hand-delivered) that you dispute the test result or the testing procedure. Request the specific substance detected and ask for information about the laboratory used and its certification status. Under Missouri Revised Statutes § 285.035, you have the right to request confirmation testing at your own expense—state this request clearly in your notice. Request that the original sample be retained and tested by a different certified laboratory. Your employer must respond within 10 business days with information about confirmation testing procedures and costs. Document all communications and keep copies. This step is critical because it creates a contemporaneous record of your objection and may be required before pursuing legal action.

Step 3: File with the Appropriate Agency. If the test was conducted improperly (no reasonable notice, non-certified laboratory, improper chain of custody), file a complaint with the Missouri Department of Health and Senior Services, Division of Regulation and Licensure (phone: 573-751-6400; website: https://health.mo.gov/). If you believe the test violated federal DOT standards and you work in transportation, file with the Federal Motor Carrier Safety Administration (FMCSA) at https://www.fmcsa.dot.gov/ or call 1-800-832-5660. If discrimination is involved (employer applied testing policies differently based on race, age, disability, or other protected status), file with the Equal Employment Opportunity Commission (EEOC) at https://www.eeoc.gov/filing-charge or call 1-800-669-4000. The EEOC office serving Missouri is located in St. Louis: 314-539-7750. You have 180 days from the violation to file an EEOC charge in Missouri (non-deferral state). Provide the EEOC with dates, test results, notice given (or lack thereof), and how the testing differed from what other employees received.

Step 4: Investigation Process and Timeline. The agency or EEOC will investigate your complaint within 30-60 days of filing. They will request your employer's testing policy, records of who was tested, laboratory certification documentation, and procedures followed in your case. The investigator will contact you for a detailed statement. Expect to wait 60-90 days for the investigation to conclude. If the agency finds a violation, they may send a formal finding or recommendation for corrective action. If discrimination is found, the EEOC may initiate a conciliation process where your employer is offered a chance to settle before litigation. Document any retaliation (adverse action taken against you after filing a complaint), as this is independently illegal under Missouri law and federal retaliation statutes.

Step 5: When to Consult an Attorney and What Type. Consult an employment attorney immediately if: (1) you were terminated after testing positive; (2) the testing facility was not certified or procedures were clearly improper; (3) you requested confirmation testing and were denied; (4) the employer is retaliating against you after filing a complaint; or (5) you were the only person or one of very few tested (possible discrimination). Contact a Missouri-licensed employment law attorney who specializes in wrongful termination or workplace rights. Many offer free initial consultations. Your attorney can send a demand letter to your employer for damages, request preservation of records, and negotiate a settlement. If settlement fails, litigation in Missouri state court or federal court (if discrimination is involved) may be necessary. Most employment cases are resolved through negotiation; litigation typically takes 12-24 months. Your attorney can explain your options for damages (lost wages, emotional distress, punitive damages if applicable) and the likelihood of success based on specific facts.