Verifying Medical Marijuana Authorization — MRO or Employer?

Due to the legalization of marijuana and its medical applications, the results of a drug test might necessarily mean an indictment for the worker. If an employee tests positive but claims to have a medical marijuana card, the employer needs to know the best course of action to take. This issue has continually plagued workplaces, so employers should know the requirements regarding the authorization of medical Marijuana.

In the United States, there are 33 states, including Washington D.C., that allow the use of Marijuana for the treatment of certain medical conditions. Though, the laws of each state differ, about 10 states prohibit employers from discriminating against qualified medical marijuana patients. This article gives more insight into whether it is the MRO or Employer who verifies medical marijuana authorization.

There are federal and state laws that subject employees to drug testing. The main groups who undergo mandatory tests are those employed in national security, as law enforcement officers, with duties to protect lives and properties, and in the health sector. These regulations help protect the health and privacy of workers but still maintain the legality of state employees engaging in drug tests.

It is up to private employers to demand this. Employers test workers periodically to maintain health and safety, workplace productivity, and stop illegal activities related to drugs. However, the laws of the state and locality also ensure that the privacy of the private employee is protected.

When is a positive drug test not a problem in the USA?

It is not every time that a worker is guilty and punished when faced with a positive drug test result in the United States. This could be due to the medical marijuana treatment, while some states allow the recreational use of marijuana. As specified by FMA Health, workers who suffer from certain medical conditions might qualify for marijuana treatment depending on the state’s regulations, and if they meet specific requirements. The conditions include:

    • Crohn’s disease
    • HIV/AIDS
  • Alzheimer’s disease
  • Epilepsy and seizures
  • Glaucoma
  • Severe nausea or vomiting caused by cancer treatment.
  • Severe and chronic pain

For medical marijuana patients with questions like where can I buy marijuana with authorization? or who have authorization to prescribe medical cannabis? etc., reaching out to their caregiver for help is important for accurate answers. They can search for “medical marijuana authorization near me” online to get the best options available and avoid trouble at work.

There are also states in the U.S that approach Marijuana as a means of generating wealth and achieving social justice. These comprise Colorado, Washington, Alaska, Oregon, Washington, D.C., California, Maine, Massachusetts, and Nevada among others. Individuals from minority communities have suffered mass incarceration due to strict marijuana laws. Therefore, these lenient states address the marijuana prohibition, with the expungement of low-level convictions.

Rules and Regulations

If you work in a safety-sensitive workplace, drug testing is carried out by a Medical Review Officer (MRO) with a federal license. However, the Department of Transportation (DOT) does not accept the authorization of medical marijuana use as a valid reason to test positive because Marijuana is considered an illegal drug with no medical use. Workers can choose an at home drug test, or try a mouth swab drug test and saliva drug test at the company’s laboratory. Home drug test are also considered to be highly precise.

When employees test positive for Marijuana in the aforementioned workplace, the laboratory informs the Medical Review Officer, who reviews the result. Then, the MRO reaches out to the worker to discuss this and requests medical evidence to support the positive result.

Due to the steady increase in number of seemingly legitimate positive test results, MROs are reconsidering their stance. DOT-regulated employers are also advised to check with their Third-Party Service Associate before disputing state-issued medical marijuana authorization.

Who is an MRO?

A Medical Review Officer is a licensed physician that reviews positive drug tests from the laboratory and evaluates possible medical explanations for the results. They are in charge of determining the accuracy of the test, if the results are legitimate, and keeping the employee’s information confidential.

In safety-sensitive work environments under the Department of Transportation, the drug screens must be reviewed by the MRO. However, in unregulated companies, the employer has the power to choose a Medical Review Officer depending on the state’s laws, though it is not compulsory.

So, if you want to ensure accurate drug test results and limit your company’s legal liability, an MRO is a perfect option. Employees can also ask the MRO questions like “does urine hold DNA” and any confusing details about the test.

DOT Drug Testing Regulations

The Department of Transportation (DOT) keeps its employees in check with regular drug tests, which screen for five major classes of drugs, including:

  •       Marijuana
  •       Cocaine
  •       Opiates – opium and codeine derivatives
  •       Amphetamines and methamphetamines
  •       Phencyclidine – PCP

Since Marijuana is classified as a Schedule 1 drug by the Federal Government, state and local laws might not apply as they are overruled by federal laws. Testing positive for THC is a big deal at trucking companies and could result in immediate termination. Even if you smoke Marijuana off duty and do not drive under the influence, THC can be detected in the bloodstream for up to 30 days. The Department of Transportation is a federal body, therefore have a zero-tolerance policy.

What is the authorization process?

Though employers cannot carry out tests without the worker’s consent, employees do not also have the right to refuse a test. Instead, the employer should inform the worker of the drug test in advance. There is a how to verify marijuana authorization form that the employee must fill out before the test.

Workplace drug testing depends on the state, nature of the job, and the worker’s position at the company. Some states allow universal testing, while some only permit random screening. Others allow testing if the employee is suspected of drug use or there is an accident. So, employers have to go through the authorization process to avoid infringing on the worker’s rights and ensure the tests are legitimate.

Workers with a recent history of marijuana consumption can learn how to pass a drug test. Depending on the testing method, they can also find out how to pass a hair follicle drug test.

Who is more protected by Law: The Boss or Worker?

If an employee refuses to take a drug test at the workplace and gets fired as a result, there might be little recourse. This would entail proving the employer wrong on the suspicions of being a safety hazard on the job.

Also, you have the chance to win your job back, if treated differently from other workers in your position. Based on FMAHealth research, anyone who is unjustly suspended on account of a drug test can make a case of the testers not following due process. No one is more protected by the law, and both the workers and employers can be held liable if guilty of misconduct during the drug testing exercise.

What can cause false-positive drug tests?

A false-positive test occurs when a substance similar to the target substance is found in the specimen, thus eliciting a positive response for an unwanted drug. This can be caused by the following:

  •       Pain killers – Advil, Aleve, Motrin
  •       Cold remedies – Benadryl
  •       Nasal decongestants – Sudafed
  •       Sleeping medication – Tylenol PM and Advil PM
  •       Diabetes medication – Metformin.
  •       Antidepressants -Zoloft etc.

How to prove a false-positive test wrong

A confirmatory test helps to rule out a false-positive result. The testing methods used for confirming the test are more sensitive and precise than panel tests, so can distinguish between the target and imposter substances. These tests include Gas chromatography-Mass Spectrometry (GC-MS) or High-performance Liquid Chromatography (HPLC).


The process of verifying medical marijuana authorization involves the employer working in tandem with the Medical Review Officer, though employees can also search for “Labcorp near me“ or “drug testing near me” online to find a laboratory for the test.

The MRO ensures a fair drug testing exercise, accurate interpretation of results, and consideration for medical marijuana patients. However, medical marijuana authorization only applies at the state and local level, as federal laws prohibit workers in safety-sensitive industries like the DOT from consuming marijuana for any reason.


  • Carolyn Gaughan

    Carolyn Gaughan is an ex-executive vice president of the Kansas Academy of Family Physicians and represents the state associations of the American Academy of Family Physicians and the American College of Osteopathic Family Physicians.