Missouri State Drug Testing Laws

Workplace Drug Testing Issues – Missouri State Laws

These categories do not affect DOT-regulated drug testing. Government employers should always call for potential additional restrictions on employee drug testing.

Workplace Drug Testing Laws in Missouri

Drug Testing Issue Status Comments
Instant or POCT Testing Restricted Use lab testing for post-accident in order to use the intoxication defense. Confirm all non-negative results at the lab.
Drug Panels No restrictions
Laboratory No restrictions SAMHSA certified highly recommended to avoid exposure to liability.
Medical Review Officer Not required Highly recommended to use an MRO for all workplace drug tests.
Random Testing No restrictions
Post-Accident No restrictions Drug testing policies should limit post-incident testing to situations in which employee drug use cannot be ruled out as potentially contributing to the incident.
Reasonable Suspicion No restrictions
Oral Fluids No restrictions
Hair Testing No restrictions
Unemployment Denial Yes
Workers Comp Discount No
Intoxication Defense Yes The law provides for a rebuttable presumption of intoxication and that the injury was proximately caused by that intoxication if certain conditions are met.
Medical Marijuana Yes November 6, 2018 - With approximately 61% of voters supporting Amendment 2, Missourians with one of 9 qualifying conditions (those without a qualifying condition can gain approval from a doctor for a medical marijuana card) will have access to purchase and/or grow medical marijuana. Employers are likely to retain the majority of their rights around marijuana pertaining to drug testing and disciplinary action, and Amendment 2 included language that protects employers from adverse action by medical marijuana-using employees.
Recreational Marijuana No
Report Driver DOT Positives No
General Statute While Missouri does not have a drug testing statute, employers must meet certain drug testing requirements in order to challenge workers' and unemployment comp claims.

Employers should maintain comprehensive drug free workplace programs and policies in order to take advantage of Unemployment Compensation Denial and Workers’ Compensation Reduction & Denial 

Intoxication Defense – Denial of Workers Compensation Claim - The Company may raise a defense to any workers’ compensation claim filed where there is a positive alcohol or controlled substance test result. This could result in a 50% reduction of benefits otherwise payable or a complete forfeiture of those benefits.

This chart is intended for informational purposes only and should not be relied upon for legal guidance. State and local law varies greatly; therefore, you are advised to consult experienced legal counsel during the development or edit of your actual substance abuse testing program and with any questions that follow.

State Law Missouri