How The ADA Direct-Threat Defense Can Defeat A Disability Claim
Not every limit posed on a disabled worker is disability discrimination. Common sense tells us that certain disabilities can prevent some people from safely performing certain jobs. At the extreme, a person with narcolepsy who unpredictably falls asleep cannot safely drive an eighteen-wheeler down the highway. A blind person cannot safely pilot a commercial airliner. A person experiencing uncontrolled seizures should not be operating a crane hundreds of feet above a construction site. And a neurosurgeon with advanced Parkinson’s disease causing severe hand tremors and impaired fine motor control cannot safely perform delicate brain surgery.
The question, therefore, is not whether it is always illegal disability discrimination to prevent a disabled employee from performing a particular job. It isn’t. The harder questions are where the law draws that line, when an employer can lawfully decide that a medical condition creates too much risk, whether a reasonable accommodation could make the work safe, and who ultimately gets to decide whether an employee is too dangerous to work.
Those questions sit at the heart of the Americans with Disabilities Act (“ADA”) and modern employment law. The ADA protects employees from disability discrimination and requires employers, in appropriate circumstances, to consider a disability accommodation that would allow a qualified employee to perform the job. At the same time, the ADA does not require an employer to ignore a genuine and significant safety risk. That is where the ADA’s “direct threat” defense comes into play.
The United States Court of Appeals for the Eighth Circuit recently confronted exactly that issue in Christensen v. Union Pacific Railroad Co., No. 25-2173, 2026 U.S. App. LEXIS 24136, 2026 WL 2320846 (8th Cir. Aug. 11, 2026). Ross Christensen had worked as a railroad conductor for more than ten years before suffering an ischemic stroke. He recovered well. His treating neurologist cleared him to return to his conductor position, his cardiologist separately cleared him to work, and a successful ablation procedure restored his heartbeat to a normal rhythm.
Union Pacific’s doctors nevertheless concluded that Christensen’s medical history created an unacceptable risk that he could suffer a future seizure. The railroad kept him from returning to his safety-sensitive conductor position. Christensen sued for ADA disability discrimination and wrongful termination
So, who gets to decide?
As Christensen shows, the answer is not automatically the employee’s treating doctor. But employers do not get to make the decision simply by saying, “Safety first.” The ADA requires something much more demanding: an individualized and objectively reasonable assessment based on current medical knowledge or the best available objective evidence.
For an employee facing medical restrictions, a denied return to work, or a rejected accommodation request, that distinction can be the difference between a lawful safety decision and unlawful ADA disability discrimination and wrongful termination. And for an employment lawyer or employment attorney evaluating the case, the real fight is often over the evidence supporting the employer’s safety judgment, whether the assessment was truly individualized, and whether a reasonable accommodation could have reduced or eliminated the claimed risk.
That is where the line gets drawn—and where ADA cases involving employee rights, disability accommodation, and claims that a disabled worker is too dangerous to work can be won or lost.
Can My Employer Decide I Am Medically Unsafe To Work?
Yes—but not every decision based on workplace safety is illegal disability discrimination. The ADA sets the bar higher than merely showing that your disability creates some risk.
The Americans with Disabilities Act recognizes what it calls the “direct threat” defense. A direct threat is: “a significant risk to the health or safety of others . . . that cannot be eliminated by reasonable accommodation.” 42 U.S.C. § 12111(3).
Two words matter: significant risk. Almost every job involves some risk, and almost every medical condition could theoretically cause something to go wrong. That is not enough. The ADA asks whether the risk is significant and whether a reasonable accommodation can eliminate it.
The seriousness of the potential harm also matters. A medical condition that presents little meaningful danger in one job may present an unacceptable danger in another.
That was the problem for Christensen. He was not working a desk job. As a Union Pacific conductor, Christensen operated and moved trains and performed switching operations.
After Christensen’s stroke, Union Pacific concluded that he faced an unacceptable risk of a future seizure. The railroad restricted him from operating company vehicles and machinery and from working on or near moving trains. In practical terms, he could no longer work as a conductor.
Importantly, the Eighth Circuit Court of Appeals did not hold that any seizure risk automatically disqualifies an employee. Instead, the nature of Christensen’s job changed the equation.
The District Court recognized that Christensen’s increased seizure risk might have been relatively low. But if a seizure occurred while he was performing his job, the potential harm “was extreme.”
The Eighth Circuit Court of Appeals made the same point when distinguishing another Union Pacific case involving an employee who suffered cardiac arrest. That employee did not hold such a safety-critical position, which the Court said “fundamentally changes the direct threat analysis.”
That is the key. The ADA does not ask whether your disability makes your job perfectly risk-free. It asks whether your particular medical condition creates a significant safety risk in your particular job that cannot be eliminated through reasonable accommodation.
But an employer cannot simply declare that such a risk exists and call it a day. Before using the direct-threat defense to defeat an ADA disability discrimination claim, the employer must conduct an individualized assessment of the employee, the medical evidence, and the actual risks of the job. That required process—and whether the employer followed it—is where Union Pacific ultimately won Christensen’s case.
Practical Tip: If your employer says your disability makes you unsafe to work, focus on the connection between the claimed medical risk and your actual job. Get your job description, medical restrictions, return-to-work releases, and accommodation requests. The question is not whether your disability creates any conceivable risk. It is whether it creates a significant risk in the job you actually perform that cannot be addressed through reasonable accommodation.
Best Disabilty Discrimination Law Firm Blogs on Point:
What Is The Process For Deciding If My Disability Makes Me Unsafe To Work?
An employer cannot look at your diagnosis, imagine the worst-case scenario, and declare you unsafe. Under the ADA, determining that an employee poses a direct threat requires an individualized assessment.
The Eighth Circuit Court of Appeals explained that the employer bears the burden of proving the direct-threat defense. Its determination must be: ”(1) the result of an individualized assessment, (2) objectively reasonable, and (3) based on the ‘most current medical knowledge and/or on the best available objective evidence.’”
The assessment must also consider four things: how long the risk will last, the nature and severity of the potential harm, how likely the harm is to occur, and how imminent the potential harm is.
In other words, the ADA requires an employer to evaluate the employee, the medical evidence, the actual job, and the actual risk—not simply the name of the disability.
Union Pacific did exactly that with Christensen, and that is why it won.
After Christensen’s stroke, Union Pacific obtained and reviewed his medical records. Its physicians initially imposed one-year sudden-incapacitation restrictions. When Christensen later sought to return to work, he provided updated medical records and underwent another fitness-for-duty evaluation.
Those updated records contained evidence favorable to Christensen. His recovery was described as “excellent.” His balance and walking were normal. He had suffered no additional neurological event. And one of his physicians concluded that he was neurologically capable of commercial driving.
Union Pacific’s physician nevertheless reached a different conclusion. After reviewing Christensen’s medical history, he determined that Christensen had an unacceptable future seizure risk. Union Pacific also considered Federal Motor Carrier Safety Administration guidance addressing seizure risk following certain strokes and intracerebral hemorrhages.
Christensen attacked that process. He argued that relying on general FMCSA guidelines meant Union Pacific had not really evaluated him individually. The Eighth Circuit Court of Appeals disagreed. Union Pacific had to evaluate Christensen’s specific medical condition—including the location of his stroke and the brain bleed he suffered during treatment—to determine whether the guideline applied to him in the first place.
The Court contrasted that process with another ADA case where an employer made only a few general calls to support its “‘prejudice, stereotypes, [and] unfounded fear’” about allowing a deaf person to drive a truck. Union Pacific’s review of Christensen, the Court said, was “more robust by orders of magnitude.”
Christensen had another seemingly powerful fact: his own doctors cleared him to work.
Still not enough.
The Eighth Circuit Court of Appeals explained: ”The question is objective reasonableness, and mere disagreement among experts does not show Union Pacific’s decision was objectively unreasonable.”
That may be the most important litigation lesson in Christensen. An employee does not necessarily defeat an employer’s direct-threat defense simply by producing a doctor who disagrees with the employer’s doctor. The employee needs evidence attacking the reasonableness of the employer’s determination.
The Court demonstrated what that evidence might look like by discussing Sanders v. Union Pacific Railroad Co. There, the employee had expert testimony that Union Pacific’s medical decision was “‘completely uncalled for, completely wrong, and not based on any medical principles at all.’” Christensen had no comparable evidence attacking the medical foundation of Union Pacific’s decision.
That difference mattered. One employee had evidence from which a jury could question whether the employer’s medical judgment was objectively reasonable. Christensen essentially had a disagreement between doctors. Under the Eighth Circuit’s analysis, those are not the same thing.
Practical Tip: If your employer claims you are a direct threat, do not focus only on getting a doctor’s note saying you can work. Find out how the employer reached its decision. Preserve the medical information you provided, fitness-for-duty evaluations, job descriptions, restrictions, accommodation requests, and communications explaining the decision. An ADA employment lawyer can evaluate whether the employer actually conducted an individualized assessment based on objective medical evidence—or simply used your disability as the reason to keep you out of work.
Best ADA Work Accommodation Attorney Blogs on Point:
How Do I Find The Best ADA Employment Lawyer Near Me?
Start by looking for an employment lawyer who regularly represents employees—not employers—in ADA disability discrimination and reasonable accommodation cases. As Christensen demonstrates, these cases can turn on much more than whether your doctor says you can work. The best ADA employment lawyer should know how to attack the employer’s claimed safety justification, determine whether the medical assessment was truly individualized, identify evidence the employer ignored, evaluate possible reasonable accommodations, and develop the medical or expert evidence necessary to get an ADA disability discrimination claim to a jury.
Spitz, The Employee’s Law Firm focuses on representing employees and protecting employee rights. We are one of the largest law firms dedicated to representing employees, which gives our employment attorneys the resources to take on employers in complex disability discrimination, failure-to-accommodate, retaliation, and wrongful termination cases. Our attorneys have extensive litigation and trial experience, and we understand that being denied the ability to work because of a disability can threaten an employee’s career, income, and family. Spitz offers free initial consultations and a no-fee guarantee, and our employment lawyers have a history of achieving great results for employees. If your employer says that your disability makes you unsafe, refuses to return you to work, denies a reasonable accommodation, or otherwise uses your medical condition against you, contact Spitz to discuss your rights and the evidence with an experienced ADA employment attorney.
Employment Lawyer Disclaimer
This employment law blog provides general information about the Americans with Disabilities Act (“ADA”), disability discrimination, reasonable accommodations, the ADA direct-threat defense, and employee rights. It is not legal advice. Every employment situation depends on its own facts, medical evidence, job duties, available accommodations, and applicable law. If your employer has refused to let you work because of a disability or medical condition, denied a reasonable accommodation, imposed medical restrictions, retaliated against you, or wrongfully fired you, consult with a qualified employment lawyer or ADA employment attorney about your specific situation.
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