Washington State Drug Testing Laws for Employers

Washington state drug testing laws don’t come from a single statute. Private employers pull their authority from common law, a 2024 cannabis-specific law that changed pre-employment screening, federal rules for transportation and safety-sensitive work, and a separate administrative code for state government employees. The result is that employers have wide latitude to test, but what they can test for, when they can test, and what they can do with the results depend on whether you’re applying for a job or already working, what kind of job it is, and whether federal law reaches your role.

The Basic Framework

No Washington statute broadly authorizes or restricts private-sector drug testing. When employees have challenged testing programs, courts have applied common law privacy principles and weighed the employer’s interest in a safe workplace against the employee’s privacy interest. In Roe v. Quality Transportation Services, the court found no clear public-policy mandate against mandatory drug testing by a private employer. That is not a blank check, but a well-designed program with a real safety rationale generally holds up.

What separates a defensible program from a shaky one is documentation. Employers need a written drug and alcohol policy in place before any test happens. The policy should identify which positions are subject to testing, what triggers a test, and what happens after a positive result or refusal. Employees have to receive the policy and acknowledge it.

Employers can test for any controlled substance recognized under federal or state law, including alcohol. Testing must follow proper collection and chain-of-custody procedures. Federally regulated programs must use laboratories certified by the Department of Health and Human Services through the National Laboratory Certification Program.¹ Private employers outside federal rules aren’t required to use HHS-certified labs, but using one strengthens the results if they’re ever disputed.

Pre-Employment Testing and the 2024 Cannabis Rule

Washington employers can require a drug test as a condition of hiring, typically after a conditional offer, and refusing the screen is generally grounds to pull the offer. Applicants must be told about the requirement and consent before the test.

The major change took effect January 1, 2024. Under RCW 49.44.240, an employer cannot discriminate against a job applicant for using cannabis off the job and away from the workplace. The law also bars employers from rejecting an applicant based on a pre-employment drug screen that detects nonpsychoactive cannabis metabolites in hair, blood, urine, or other bodily fluids.² Those metabolites indicate past use, not current impairment.

The cannabis protection is narrow. It applies only to pre-employment screening. It does not limit an employer’s ability to maintain a drug-free workplace, run post-accident testing, or test a current employee for suspected impairment.² Applicants can still be screened for every other controlled substance without restriction.

Jobs Not Covered by the Cannabis Protection

RCW 49.44.240 lists seven categories of jobs where employers can still screen applicants for cannabis metabolites and act on the results:

Positions requiring a federal government background investigation or security clearance.²
Positions with a general authority Washington law enforcement agency.
Positions with fire departments, fire protection districts, or regional fire protection service authorities.
Any other first responder role, including 911 dispatchers and emergency medical services providers.
Corrections officers at jails, detention facilities, or the Department of Corrections, along with anyone directly responsible for the custody, safety, and security of confined individuals.
Any position in the airline or aerospace industries.
Safety-sensitive positions where impairment presents a substantial risk of death, but only if the employer designated the position as safety-sensitive before the applicant applied.

The statute also does not override any state or federal law that independently requires drug testing as a condition of employment, federal funding, or a federal license or contract.² Where federal law requires cannabis testing for a job, the Washington rule steps aside.

Testing Current Employees

Once you’re on the payroll, the rules tighten. Blanket or random testing of most workers is disfavored, and an employer generally needs a concrete reason to test.

Reasonable Suspicion

The most common trigger is reasonable suspicion of impairment. The employer must have specific, observable facts: bloodshot eyes, slurred speech, the smell of alcohol, erratic behavior, an unexplained drop in performance. Hunches or personal dislike do not qualify. Employers should document what was observed, ideally from more than one supervisor, so the record holds up if discipline follows.

Post-Accident Testing

An employer can test after a workplace accident if there’s a reasonable basis to think substance use played a role. Federal OSHA rules add a limit: under 29 CFR 1904.35(b)(1)(iv), employers cannot retaliate against workers for reporting a work-related injury.³ OSHA has clarified that most post-accident testing is fine as long as it serves the legitimate purpose of investigating what caused the incident. A blanket policy of testing everyone who reports any injury can look retaliatory. OSHA guidance recommends testing all employees whose conduct could have contributed to the incident, not just the person who was hurt.⁴

Random Testing

Random testing of current employees is generally only defensible in Washington for safety-sensitive positions or roles under federal testing mandates. For most office, retail, or similar work, random testing without individualized suspicion is hard to justify.

Whatever the trigger, testing has to follow the written policy, and results are confidential. They should only be shared with people who have a legitimate need to know.

Safety-Sensitive and Federally Regulated Roles

Safety-sensitive work is the main exception to Washington’s skepticism of random testing. The most heavily regulated category is workers covered by Department of Transportation rules: commercial motor vehicle drivers, pipeline workers, railroad employees, transit operators, and certain aviation and maritime workers. These roles fall under mandatory federal testing programs in 49 CFR Part 40, which include pre-employment, random, post-accident, reasonable suspicion, return-to-duty, and follow-up testing.⁵ Washington’s cannabis protection does not apply.

The DOT panel covers marijuana, cocaine, amphetamines, opioids (including semi-synthetic opioids like hydrocodone and oxycodone), and phencyclidine. DOT urine collections use a split-specimen method, meaning the sample is divided so the employee can later request that the second bottle be tested at a different lab if the first comes back positive.⁶

Other jobs commonly treated as safety-sensitive include roles involving firearms, dispensing medication, operating heavy machinery, or public safety duties. Under Washington’s cannabis law, an employer designating a role as safety-sensitive has to make that designation before the applicant applies, not after a positive test.²

Prescription Medications

Legally prescribed medications can trigger positives on standard panels. Opioid painkillers, some ADHD medications, benzodiazepines, and certain sleep aids all show up.

Under the Americans with Disabilities Act, a drug test is not a medical examination, and the ADA neither prohibits nor authorizes drug testing.⁷ The ADA does protect employees with disabilities who take prescribed medication. If a positive is caused by a prescription and the employer takes adverse action without looking further, the employee may have a disability discrimination claim. The employer’s obligation is to engage in an interactive process rather than treat every positive as automatic grounds to fire.

If you take a prescription that could affect a test, disclose it to the Medical Review Officer or test administrator. That information is confidential medical information and must be kept in a separate file from your regular personnel records. You can also ask the lab to run confirmatory testing that distinguishes a prescription from illicit use.

Challenging a Result

Under DOT-regulated testing, the process is defined. After the Medical Review Officer notifies you of a verified positive, you have 72 hours to request testing of the split specimen. The request can be verbal or written. The MRO directs the original lab to forward the sealed second bottle to another HHS-certified lab, and the first lab cannot share identifying information with the second.⁸ If the retest fails to confirm the original positive, the result is cancelled.

For non-DOT testing, the challenge process should be in the employer’s written policy. Many private employers voluntarily use split-specimen procedures to protect themselves. If the policy is silent, you can still request a retest, but absent a contract or collective bargaining obligation, the employer isn’t required to grant one. Read the policy before you ever get tested.

What Happens After a Positive or a Refusal

Washington is an at-will employment state, and a positive test or a refusal is generally grounds for termination if the employer followed its written policy. Consequences vary by policy. Some employers terminate immediately; others use last-chance agreements or refer employees to an assistance program.

If you file for unemployment after being fired for a positive test, expect the claim to be contested. Under RCW 50.20.060, an employee discharged for misconduct connected with work is disqualified from benefits for a period and must earn a set amount at a new covered job before regaining eligibility. Whether a positive test counts as misconduct depends on the facts: violating a clearly communicated policy is more likely to qualify than a borderline case where the rules were vague or you had no notice. The statute also states that alcoholism is not a defense to misconduct disqualification.⁹

Workers’ compensation works differently. Washington does not automatically deny workers’ comp benefits when an injured worker tests positive. A positive test after a workplace injury can complicate the claim and prompt more investigation, but the Department of Labor and Industries generally evaluates the injury on its own merits. The question that matters is whether substance use was the proximate cause of the injury, not just whether something was in your system.

State Government Employees

If you work for a Washington state agency in a civil service role, a separate rule applies. WAC 357-37-200 lets an agency require testing when it has a written policy meeting legal requirements and there’s a qualifying reason, including specific objective grounds to believe work performance is impaired or involvement in an on-duty accident described in the policy. Certain designated positions can be tested without individualized suspicion, including roles providing security on state property, ensuring public safety, administering or dispensing medication, or using a firearm as part of job duties.¹⁰

1
SAMHSA. Certified Laboratory List
2
Washington State Legislature. Washington Code RCW 49.44.240 – Discrimination Based Upon Cannabis Use Exceptions
3
eCFR. 29 CFR 1904.35
4
Occupational Safety and Health Administration. Clarification of OSHA’s Position on Workplace Safety Incentive Programs and Post-Incident Drug Testing Under 29 CFR 1904.35(b)(1)(iv)
5
eCFR. 49 CFR Part 40 – Procedures for Transportation Workplace Drug and Alcohol Testing Programs
6
eCFR. 49 CFR Part 40 Subpart E – Specimen Collections
7
Office of the Law Revision Counsel. 42 U.S. Code 12114 – Illegal Use of Drugs and Alcohol
8
eCFR. 49 CFR Part 40 Subpart H – Split Specimen Tests
9
Washington State Legislature. Washington Code RCW 50.20.060 – Disqualification From Benefits Due to Misconduct
10
Washington State Legislature. Washington Administrative Code WAC 357-37-200