Drug Testing

Overview

Drug testing is different from every other part of a background check. A criminal record already exists in a courthouse and the check simply locates it. A drug test creates new information about a person at the moment it is taken.

That difference drives most of the law. Because the employer is ordering a medical procedure rather than looking up a public record, states regulate when testing may happen, how the sample must be handled, and what the employer may do with the result. Those rules vary more than almost any other area of employment screening.

Marijuana is where the variation is sharpest, and it is the reason most people arrive at this page. 12 states protect off-duty use, 13 protect registered medical patients only, and 26 protect neither.

Why Employers Test

Drug testing programs generally exist for one of 4 reasons:

• Safety. Positions involving vehicles, heavy equipment, heights, or patient care carry real consequences from impairment.
• Federal requirement. Transportation, aviation, pipeline, and defense roles are required to test under federal regulations, and the employer has no discretion about it.
• Insurance and workers compensation. Several states offer a workers compensation premium discount to employers who follow a state approved drug free workplace program.
• Client or licensing requirements. Hospitals, schools, and government contractors frequently require testing as a condition of the contract.

A test result tells an employer what was in someone’s system. It does not, on its own, tell the employer whether that person was impaired at work. That gap is the source of nearly every dispute in this area.

When Testing Happens

Most programs test at some combination of these points. Which ones an employer may use depends heavily on state law.

Types of Tests and What They Detect

The method chosen determines the detection window, meaning how far back the test can reach. It does not determine whether the person was impaired.

• Urine is the most common by a wide margin and the only method permitted for federally regulated testing. It typically detects use within the past few days, though heavy marijuana use can register for weeks.
• Oral fluid catches very recent use, generally within a day or so, which makes it useful after an accident or where impairment is suspected.
• Hair reaches back roughly 90 days but misses recent use entirely, since it takes time for hair to grow out.
• Blood is invasive and rarely used outside accident investigations, but it comes closest to measuring current impairment.
• Sweat patch is worn for a period of days or weeks and captures use during that window.

Our article on types of drug tests explained covers each method in more detail.

What a Drug Panel Covers

A panel is simply the list of substances a test screens for. Larger panels cost more and catch more.

The 5 Panel

This is the federal standard and the most widely used private sector panel. It covers marijuana, cocaine, amphetamines including MDMA, opioids, and PCP. The opioid category was expanded in 2018 and now reaches common prescription painkillers such as hydrocodone, oxycodone, hydromorphone, and oxymorphone, not just heroin and codeine.

The 10 Panel

Adds substances typically obtained by prescription, including barbiturates, benzodiazepines, methadone, and propoxyphene. Employers in healthcare and safety sensitive industries often choose this level.

Expanded Panels

Panels of 12 or more can add synthetic opioids, alcohol, and other substances an employer identifies as a risk. Fentanyl has been proposed for addition to the federal panel but is not part of it as of 2026.

One important limit: federally regulated tests may not screen for anything beyond the defined federal panel. A DOT test cannot be quietly expanded.

Marijuana and State Law

This is the most misunderstood area in employment screening, and the most common mistake is assuming that legalization creates employee protection. It does not. They are separate questions decided by separate laws.

Colorado is the clearest example. Recreational marijuana has been legal there for over a decade, and the state has a statute protecting lawful off-duty activities. The Colorado Supreme Court held in Coats v. Dish Network that the statute does not cover marijuana, because marijuana remains illegal under federal law. Employers there may still enforce zero tolerance policies. Michigan, Ohio, and Oregon reach the same result by different routes.

Where the 51 Jurisdictions Stand

New York Goes Furthest

New York does not merely restrict acting on results. It generally prohibits testing for cannabis at all, unless federal or state law requires it, federal funding or contracting requires it, or the employee shows specific, articulable signs of impairment on the job. The statute expressly says that the smell of cannabis and a positive test are not enough on their own.

The Metabolite Rule

4 jurisdictions bar an employer from acting on a test that detected only non-psychoactive metabolites: California, the District of Columbia, New Jersey, and Washington. The reasoning is scientific rather than political. Metabolites establish past use, not present impairment, so a result showing metabolites alone proves nothing about the workday in question.

New Jersey Requires a Trained Evaluator

New Jersey pairs the test with a person. To discipline an employee for cannabis impairment, the statute contemplates both a positive test and an evaluation by a certified Workplace Impairment Recognition Expert. It is the only state that builds a trained human observer into the process this way.

Two States Protect Only Government Workers

Louisiana and Utah both appear on lists of states with marijuana employment protections, and both protections apply only to public employees. A private employer in either state may test and act on the result without restriction. This is a common trap in summaries that do not distinguish public from private employment.

Safety Sensitive Carve-Outs Are Nearly Universal

Almost every protective state exempts safety sensitive positions, and several let the employer define what counts. Oklahoma and South Dakota give employers particularly broad discretion in drawing that line. Federal contract and federal funding exceptions appear in most of these statutes as well.

You can confirm the current rule for any state on our state background check law pages.

Other State Testing Rules

Marijuana gets the attention, but several states regulate the mechanics of testing regardless of substance.

Procedure Requirements

North Carolina does not require anyone to test, but any employer that does must follow the Controlled Substance Examination Regulation Act, which governs sample collection, requires a positive screen to be confirmed by a second reliable method, and lets the person keep a portion of the sample for independent testing.

Vermont goes further than any other state. An applicant may be tested only after a conditional offer and only with advance written notice. A current employee may be tested only where there is probable cause to believe they are using or impaired on the job. Random and company-wide testing are prohibited outside federally regulated roles. An employer may not fire an employee for a first positive result if the employee agrees to complete an assistance program.

Notice, Cost, and Retest Rights

• Alaska protects employers from certain lawsuits if they adopt a written policy and give employees written notice at least 30 days before testing begins.
• Arkansas requires that any employer mandated drug test be provided at no cost to the applicant or employee, with a free copy of the results on request.
• Nevada lets an employee tested within the first 30 days of employment pay for a second test to rebut the first result.
• Maine prohibits cities and counties from writing their own drug testing ordinances, so the statewide rule is the only one that applies.

Voluntary Drug Free Workplace Programs

Several states, including Georgia and Alaska, operate voluntary programs that offer employers a workers compensation premium discount or a measure of legal protection in exchange for following prescribed testing procedures. Participation is optional, but once an employer opts in, the procedures become mandatory for them.

What Happens After a Positive Result

A positive screening result is not a final answer, and treating it as one is a common and costly error.

Screening, Then Confirmation

The first test is a fast, inexpensive screen. It is designed to catch anything above a cutoff level, which means it produces false positives. Anything that screens positive must be confirmed by a far more precise laboratory method before it means anything. Federal rules set both cutoffs. For marijuana, the screening cutoff is 50 nanograms per milliliter and the confirmation cutoff is 15.

The Medical Review Officer

In federally regulated testing, and in most well run private programs, a confirmed positive goes to a Medical Review Officer before it reaches the employer. The MRO is a licensed physician trained to review results.

The MRO contacts the employee directly and privately, and asks whether there is a legitimate medical explanation, such as a valid prescription. If there is, the MRO reports the test to the employer as negative. The employer never learns what the medication was. This step exists specifically to keep an employer from learning private medical information it has no right to.

One critical limit applies in federally regulated testing. A legitimate medical explanation must be a federally legal prescription. A state medical marijuana card, a dispensary receipt, or a physician’s recommendation carries no weight with a DOT MRO, no matter what the state law says.

The Right to a Retest

Under federal rules the sample is split at collection. An employee who receives a verified positive may request that the second portion be tested at a different certified laboratory, at their own expense in most programs. Several states extend a similar right to non-federal testing.

The Rules Employers Must Follow

Three rules govern testing programs. Each has its own page on this site, so this is the summary.

Write the Policy Down and Apply It Consistently

A written policy stating who is tested, when, for what, and what happens after a positive result is the single best protection an employer has. Applying it unevenly is what turns a positive test into a discrimination claim.

Know Whether the FCRA Applies

When an employer contracts directly with a laboratory, the result is generally not a consumer report and the FCRA does not govern it. When a background screening company arranges the test and reports the result as part of a broader report, it usually does. If the FCRA applies, so do the disclosure, authorization, and rejection procedures. See our FCRA overview.

Follow the Steps Before Rejecting Someone

Where the FCRA applies, an employer cannot simply issue a rejection. It must send a preliminary notice with a copy of the report, allow time to respond or correct an error, and only then issue the final decision. See the adverse action process.

For Applicants

If you are the one being tested, a few things are worth knowing before you provide a sample.

• Tell the Medical Review Officer about prescriptions, not the employer. The MRO is a physician bound to keep the details confidential, and a valid prescription generally converts a positive into a reported negative. Disclosing medications to a hiring manager instead gives away private health information with no benefit.
• A positive screen is not the end. Screening tests produce false positives by design. Ask whether the result was confirmed by laboratory testing before you accept it.
• You can usually request a retest. Federal testing splits your sample at collection precisely so a second portion can be tested elsewhere. Ask about the split specimen procedure.
• Check your state on marijuana. A positive marijuana test carries very different consequences depending on where you work, and in 12 states off-duty use is protected outright.
• A medical card does not help in federally regulated jobs. For DOT covered positions, state medical marijuana authorization is not a defense.
• If a screening company reported it, you can dispute it. Our guide to disputing a background check covers the process.

Best Practices

• Put the testing policy in writing and give it to employees before any testing begins
• Define which positions are safety sensitive and why, in writing, before you need to rely on it
• Test the same way for every person in the same role
• Never act on a screening result that has not been confirmed by laboratory testing
• Route confirmed positives through a Medical Review Officer so you never receive private medical details
• Check the marijuana rule for the state where the work is performed, not where the company is based
• Train supervisors on documented observation before allowing reasonable suspicion testing
• Review the policy annually, since this area of state law changes faster than any other in screening

Frequently Asked Questions