COVID-19 Vaccination Requirements: Potential Constraints on Employer Mandates Under Federal Law
Legal Sidebar
COVID-19 Vaccination Requirements:
Potential Constraints on Employer Mandates
Under Federal Law
February 10, 2021
The COVID-19 pandemic has forced unprecedented workplace changes and raised a host of legal issues.
Employers may struggle with how to protect workers from infection, avoid disruptions that may result
from sick leave and employee quarantines, and manage potential liability if an employee contracts the
virus at work. Some have noted employers’ plans to encourage or require COVID-19 vaccinations for
workers as they become available. Policies will undoubtedly vary. Observers expect that health care,
travel, and retail businesses will more likely mandate or encourage vaccines, while those with less
customer interaction and more work-at-home capacity may defer to employee choice on whether to seek
vaccination. Some expect that smaller businesses, too, may be more likely to require vaccination, because
a wave of infection among a smaller staff could shut down operations. In accordance with guidance from
the Centers for Disease Control and Prevention (CDC), many health care providers already mandate
annual flu vaccination, providing an informative precedent for COVID-19 vaccination policies.
Whatever approach vaccination-policy decisionmakers consider, federal antidiscrimination statutes,
among other laws, may inform, and perhaps constrain, the implementation of vaccination mandates.
Federal civil rights laws do not bar vaccination mandates by private and state government employers, but
they may affect their scope. Some laws, for example, restrict employers from making certain medical
examinations or inquiries, while others require employers to consider workers’ religious objections to
vaccination and potential disabilities preventing vaccination. The coronavirus pandemic is unique and,
thus far, courts have not evaluated vaccination requirements in this context. But the Equal Employment
Opportunity Commission (EEOC), which enforces these federal civil rights laws in employment, has
issued guidance on COVID-19 and vaccination policies. In addition, an underlying principle of many
employment antidiscrimination laws that call for accommodation is reasonableness. Concerns about
employees spreading COVID-19 will likely weigh heavily in any challenge to a vaccine mandate.
This Sidebar provides a general background, in light of recent EEOC guidance and courts’ prior
adjudication of employer vaccine mandates, on federal antidiscrimination statutes (including the
Americans with Disabilities Act [ADA] and Title VII of the Civil Rights Act of 1964) relevant to
employers or lawmakers crafting vaccination requirements. In addition, the Sidebar briefly considers
Congressional Research Service
https://crsreports.congress.gov
LSB10573
CRS Legal Sidebar
Prepared for Members and
Committees of Congress
Congressional Research Service
2
other laws that could constrain employer vaccine mandates, including the Religious Freedom Restoration
Act (RFRA). RFRA may limit some government employers’ adoption of vaccine mandates and affect
future legislation governing vaccine mandates, even legislation that would compel private employers to
adopt vaccine mandates or require certain categories of employees to be vaccinated. Finally, the Sidebar
concludes by identifying potential legislative options for Congress to clarify how these statutes apply in
pandemic circumstances.
Federal Civil Rights Laws and Employee Vaccination Policies
While federal employment antidiscrimination law does not bar employers from requiring vaccinations, it
does require employers to make certain exemptions for employees with disabilities or religious concerns.
The ADA and the Rehabilitation Act of 1973 (applying ADA standards to federal employers and grant
recipients) require employers to make changes to work rules for some employees with disabilities. These
laws would apply to employer vaccine mandates. Disability laws also restrict certain medical inquiries.
Second, Title VII of the Civil Rights Act of 1964 requires employers to take into account workers’
religious objections to vaccination and health concerns of pregnant employees.
Title VII and federal disability protections apply to most state, federal, and private employers. These laws
have a number of exemptions. Of particular relevance, neither the ADA nor Title VII applies to employers
of fewer than 15 workers. To date, there is little case law regarding how these statutes might apply to
COVID-19 vaccination policies, but case law concerning other vaccination policies, along with EEOC
guidance concerning COVID-19 specifically, may be instructive.
Reasonable Accommodations for Employees with Disabilities
In the context of COVID-19, some workers may request an exemption from mandatory vaccination
because of a medical condition. If an employee’s medical condition amounts to a disability—that is, an
“impairment that substantially limits one or more major life activities”—then the ADA or the
Rehabilitation Act apply, barring employers from taking adverse action against a worker because of
disability. Further, federal disability law requires employers to provide requested reasonable
accommodations unless they would impose an undue hardship on the employer. In considering an
accommodation request, an employer must assess whether a disability precludes vaccination, available
alternatives, and (in the case of an infectious disease) possible threats from vaccine exemptions.
Coronavirus Vaccination Risks and Disability
While much remains unknown, reports suggest that people with some medical conditions may not be able
to receive a COVID-19 vaccination. For example, vaccine manufacturer Pfizer states that its vaccine
should not be given to anyone with a known history of severe allergic reaction to a component of the
vaccine. In accordance, the CDC recommends that anyone with an allergy to an ingredient in one of the
COVID-19 vaccines should not receive that vaccine. What is more, people who have had an allergic
reaction to another vaccine—even a mild reaction, the CDC says—should consult with a doctor about
getting a COVID-19 vaccine. The CDC emphasizes, however, that the coronavirus and responding
vaccines are new, and data on COVID-19 vaccination for some populations are limited.
Whenever an employee raises medical concerns about vaccination, employers must consider whether
disability laws require an accommodation, including a possible exemption. Depending on work
circumstances, potential accommodation for an unvaccinated employee might include temporary job
restructuring, work at home, distancing from coworkers or customers, or other measures. In the end, if a
worker cannot get vaccinated for reasons of disability or (as discussed below) religion, and a reasonable
accommodation is not possible, the EEOC acknowledges that the employer may bar the employee from
the workplace.
Congressional Research Service
3
Direct Threat Exception to Reasonable Accommodation
In general, when a worker requests a modification in working conditions because of a disability, an
employer must ordinarily evaluate whether it can provide a reasonable accommodation. During the
COVID-19 emergency, while employers must still consider accommodation requests, some might make
use of a provision in the ADA that provides that an employer need not accommodate an employee who
poses a “direct threat.” Under it, employers may exclude employees with disabilities if their presence
would create “a significant risk of substantial harm to the health or safety of the individual or others that
cannot be eliminated or reduced by reasonable accommodation.” The EEOC has concluded that this
provision applies in pandemic circumstances, permitting employers to keep infected employees out of the
workplace.
In some cases, this rule might also justify barring an unvaccinated worker from the workplace, even if
disability prevents vaccination. Use of this exception, however, first requires an individualized, objective
assessment of the risk the unvaccinated employee presents. The risk’s duration, imminence, the likelihood
of harm, and the degree of harm are all relevant. All in all, the EEOC suggests that in the case of COVID-
19 vaccination a “conclusion that there is a direct threat would include a determination that an
unvaccinated individual will expose others to the virus at the worksite.” An employer should consider
workplace-specific factors, such as “[t]he prevalence in the workplace of employees who already have
received a COVID-19 vaccination and the amount of contact with others, whose vaccination status could
be unknown.” More generally, the EEOC has clarified that “[t]he ADA and the Rehabilitation Act do not
interfere with employers following advice from the CDC and other public health authorities on
appropriate steps to take relating to the workplace.”
Courts’ Assessments of Mandatory Vaccination Under Federal Disability Statutes
Courts have yet to assess mandatory vaccine requirements during the COVID-19 pandemic, but they have
occasionally reviewed challenges to mandatory flu vaccination requirements under civil rights statutes. In
many cases employers have prevailed, including when an employee did not prove that she had an alleged
allergy and did not seek out available hypoallergenic vaccines. In another case, a court concluded that an
employee could not show she had a disability if she did not prove that her allergy substantially limited a
major life activity.
In other circumstances, judges have looked more favorably on an employee’s requests. The Third Circuit
concluded that severe anxiety over an injection might qualify as a disability, at least in the case of a nurse
who refused a tetanus, diphtheria, and pertussis vaccine. The court held that a plaintiff had sufficiently
raised an ADA claim, given that she proposed wearing a mask instead of getting a vaccine and her
employer rejected the offer without proposing any alternative.
Religious Accommodations Under Title VII
Title VII similarly requires employers to accommodate workers’ religious practices unless they impose an
“undue hardship on the conduct of the employer’s business.” As a general matter, this Title VII provision
applies when an employee’s religious belief or practice conflicts with a job requirement.
In the context of vaccine objections, courts have examined a variety of religious beliefs and possible
accommodations. In one such case, a Muslim worker in a Boston hospital sought an exemption to a flu
vaccine citing concerns about pork ingredients. The defendant generally accommodated employees’
opposition to pork-based ingredients with a gelatin-free flu vaccine. But while this accommodation
resolved other workers’ religious concerns, plaintiff believed many vaccines were “contaminated.” The
hospital also tried to accommodate plaintiff by finding her a position outside of patient care, but did not
succeed. The court held that the hospital had reasonably accommodated plaintiff when it helped her seek
Congressional Research Service
4
an alternate position and held, in the alternative, that retaining her would have imposed an undue
hardship. The record showed the hardship of infection risk, the court concluded, because it documented
“the Hospital’s understanding of the medical consensus on influenza vaccination” for health care workers.
In the Title VII accommodation context, courts have held that an “employer suffers undue hardship when
required to bear a greater than de minimus [sic] cost or imposition upon co-workers” for religious
adjustments. Whether an accommodation is an undue burden takes into account other employees’ rights,
efficiency, cost, and other considerations. The Supreme Court has explained that Title VII does not require
accommodations that come “at the expense of others.” For example, when an employee sought a
particular work schedule to accommodate Sabbath observance, the Court concluded that Title VII did not
require an employer to modify other workers’ seniority rights to provide the accommodation.
In further defining what qualifies as a religious practice, EEOC regulations include “moral or ethical
beliefs . . . held with the strength of traditional religious views.” This encompasses idiosyncratic beliefs,
which “no religious group espouses,” or those “the religious group to which the individual professes to
belong may not accept.” Ordinarily, the EEOC recommends, employers should “assume that an
employee’s request for religious accommodation is based on a sincerely held religious belief.” But if there
is “an objective basis for questioning either the religious nature or the sincerity of a particular belief,” the
employer may request additional supporting information.
Courts have considered a range of beliefs. For example, a district court in Ohio found it “plausible” that a
hospital employee refusing an animal-based flu vaccine “could subscribe to veganism with a sincerity
equating that of traditional religious views,” given that she cited Bible verses as support.
In other cases, courts have concluded that an objector’s beliefs, however strongly held, were not religious
in nature and thus did not qualify for legal protection. For example, the Third Circuit, considering an
objection to a mandatory flu vaccine, concluded that an employee’s “personal belief[]” that “the flu
vaccine may do more harm than good” amounted to “a medical belief, not a religious one” under Title
VII. Although the employee cited a passage attributed to Buddhism in his complaint, he did “not belong
to any religious organization.” And the employee’s belief that “one should not harm their [sic] own body”
was, in the court’s view, an “isolated moral teaching” rather than “a comprehensive system of beliefs.” In
a similar vein, the Second Circuit rejected a religious challenge in another context, school vaccination
requirements. It upheld a finding that parents’ “strong convictions concerning the necessity of a ‘natural
existence,’” grounded in “scientific and secular theories” were not religious.
Vaccination and Pregnant Employees
Pregnant women, as well, may have particular medical concerns and they enjoy legal protections under
federal civil rights laws. While data are limited, the CDC has yet to identify specific safety concerns
about pregnancy and COVID-19 vaccinations. But the CDC has suggested that “a discussion with a
healthcare provider might help” a pregnant woman “make an informed decision” about vaccination.
Three civil rights statutes may be relevant to vaccine mandates for pregnant employees. The Pregnancy
Discrimination Act (PDA), a component of Title VII, protects pregnant workers but does not expressly
require accommodation. It mandates pregnant women “be treated the same ... as other persons not so
affected but similar in their ability or inability to work.” In general, it might be argued that the PDA bars
employers from offering some workers vaccine exemptions while denying them to pregnant women.
Two disability statutes, the ADA and Rehabilitation Act, also protect some pregnant women. If a
pregnancy-related complication is so limiting that it amounts to a disability then, whether or not tied to
the pandemic, the pregnant employee enjoys ADA and Rehabilitation Act protections. These include
accommodations when reasonable. Beyond that, several state statutes require reasonable accommodations
for pregnant workers by state or private employers regardless of disability.
Congressional Research Service
5
Medical Examinations or Inquiries Under the Americans with Disabilities Act and
the Rehabilitation Act
In addition to requiring reasonable accommodation, federal disability laws restrict some medical
examinations and inquiries, and they do so for all employees—not just those with disabilities. If an
employer imposes a medical examination or asks about potential disability, the test or inquiry must be
“job-related and consistent with business necessity.”
In the case of COVID-19 vaccinations, the EEOC has stated that a vaccination itself is not a medical
examination. Further, the agency has concluded that requiring proof of vaccination is not a disability-
related inquiry under the ADA. In the agency’s view, employers may generally require vaccinations and
ask for documentation. Courts have yet to evaluate vaccination requirements in a pandemic setting.
Unlike the vaccination procedure itself, pre-vaccination screening questions might implicate the ADA and
Rehabilitation Act, if they elicit information about a disability. The EEOC explains that “[i]f the employer
administers the vaccine, it must show that such pre-screening questions it asks employees are ‘job-related
and consistent with business necessity.’” To meet this standard, “an employer would need to have a
reasonable belief, based on objective evidence, that an employee who does not answer the questions and,
therefore, does not receive a vaccination, will pose a direct threat to the health or safety of her or himself
or others.”
This same rule would apply if employers ask questions about workers’ disabilities in order to prioritize
vaccination for certain at-risk groups. Once an employer had acquired employees’ medical information,
disability laws require it be kept confidential.
Under the current federal framework, a voluntary, employer-administered vaccination requirement would
appear to avoid these concerns, since employees could decline the vaccine and related questions. What is
more, if a third party (not under contract with the employer) administers a required screening and
vaccination, screening questions would not violate the disability laws.
Considerations Under the Religious Freedom Restoration Act
and Other Laws
Under the federal laws discussed above, if an employer cannot reasonably accommodate a worker’s
disability or religious practice, the employer may exclude the employee from the workplace. But before
terminating an unvaccinated worker, employers must consider other potential employee protections.
The Religious Freedom Restoration Act (RFRA) prohibits the federal government and other covered
entities like the District of Columbia and Puerto Rico from “substantially burden[ing]” a person’s exercise
of religion except in limited circumstances. RFRA authorizes a person “whose religious exercise has been
burdened in violation” of the statute to sue the government. In such an action, the government may need
to show that the burden imposed furthers a “compelling governmental interest” and is “the least restrictive
means” of furthering that interest. RFRA’s standard is thus more rigorous than Title VII’s religious
accommodation standard, for which the touchstone is reasonableness. (RFRA also provides more robust
protections from application of facially neutral laws and policies than the First Amendment’s Free
Exercise Clause, which the Supreme Court has construed as not normally providing a basis for
noncompliance with generally applicable laws and policies. However, the scope of that Clause’s
protections is currently the subject of a pending Supreme Court case.) Many states have adopted their
own versions of RFRA.
RFRA could apply in the context of workplace COVID-19 vaccination in two ways. First, if the federal
government or a covered entity as a regulator passes a law or adopts a rule mandating vaccination for
certain public or private employees, employees with religious objections may have a cause of action
Congressional Research Service
6
against the government under RFRA. (RFRA provides that new federal statutes must “explicitly
exclude[]” RFRA’s application if Congress does not want RFRA to apply to that law.) Likewise, if the
law or rule imposes vaccination obligations on private employers, employers with religious objections
may also have a RFRA claim. Second, if the federal government or a covered entity as an employer
adopts its own policy requiring its employees to be vaccinated, employees with religious objections could
bring a RFRA claim against their government employer—although some courts might limit their remedy
to Title VII. Federal appellate courts have split on whether Title VII provides the “exclusive” remedy for
employees seeking religious accommodations from their government employers, or whether plaintiffs can
bring separate claims under RFRA and Title VII. The Supreme Court has not yet opined on RFRA’s
relationship with Title VII, but in Bostock v. Clayton County, the Court recently posited that “[b]ecause
RFRA operates as a kind of super statute, displacing the normal operation of other federal laws, it might
supersede Title VII’s commands in appropriate cases.”
Assuming that an employee in an RFRA action were to demonstrate a “substantial burden” on the
employee’s religious exercise, cases involving other compulsory vaccination programs suggest strong
governmental interests behind immunization efforts against infectious diseases. However, applying RFRA
in the context of a COVID-19 gathering restriction in the District of Columbia, a federal district court
cautioned that a government’s “generalized interests” in “combating the COVID-19 pandemic” may not
rise to the level of “compelling” under RFRA unless the government can show a compelling reason to
apply its policy to “the particular claimant whose sincere exercise of religion is being substantially
burdened.” Moreover, whether a particular law or policy is the “least restrictive means” of furthering
public health-related interests likely depends on the particulars of the law or policy and any exemptions or
accommodations.
Many employees, both in government and the private sector, have additional rights. An employee may be
entitled to leave under the Family and Medical Leave Act (FMLA) or specific coronavirus relief
measures. In some workplaces, a mandatory vaccination regime may require union approval. Local and
state labor laws or local coronavirus health measures may apply. Potential vaccination prescreening
questions, in addition to raising ADA issues, may implicate the Genetic Information Nondiscrimination
Act (GINA). Concerns may arise if prescreening questions seek genetic information, perhaps in the form
of family members’ medical histories. In considering vaccination policies, employers may also be mindful
of a range of other authoritative recommendations and legal requirements, including CDC advisories,
local public health directives, and guidance from the Occupational Health and Safety Administration.
Considerations for Congress
There is still much uncertainty about applying various antidiscrimination statutes in pandemic
circumstances. For example, Title VII, the ADA, and the Rehabilitation Act each require individualized
assessments of whether an accommodation must be granted to a particular employee, making it difficult
to predict how employers, agencies, and courts will apply them to widespread COVID-19 risks and
whole-workforce vaccination policies. In addition, it may be hard for employers to make some of the
required decisions and evaluations quickly, because the statutes require an interactive process that allows
for back-and-forth communication, input from medical providers, and case-specific analysis.
To facilitate a more uniform response, Congress might opt to specify whether or not unvaccinated
employees, or certain categories of unvaccinated employees (taking into account their interactions with
vulnerable populations) present a “direct threat” under the ADA in the pandemic exigency. Considering
that accommodation provisions permit workers to request modifications to any workplace rule, Congress
could consider exempting vaccination policies during the pandemic from ADA, Rehabilitation Act, and
Title VII coverage. Alternatively, Congress could specify whether specific protective measures, such as
isolation or wearing protective gear, constitute reasonable accommodations. In addition, Congress might
Congressional Research Service
7
modify existing ADA and Rehabilitation Act restrictions on employers asking disability-related questions
to facilitate vaccination and to prioritize at-risk vaccination candidates.
With respect to RFRA, Congress could clarify its interplay with Title VII. If Congress were to expressly
extend RFRA to covered governmental entities as employers, then employees with religious objections
could attempt to show that their employer’s vaccination policy imposes a substantial burden on their
religious exercise. Alternatively, Congress could expressly provide that Title VII is the exclusive remedy
in cases involving religious objections by employees against government employers that are covered
entities under RFRA. Or, Congress could take the broader step of exempting vaccination policies from
RFRA if Congress decides that RFRA’s heightened standard of review should not apply.
Leaving aside existing statutes, Congress could opt for independent legislation with specific rules for
pandemic-related workplace safety. Provisions might address vaccination, procedures for exemption,
COVID-19 testing, leave, reassignment, and protective equipment.
Congress could also consider measures to fund, mandate, or support voluntary workplace vaccination
campaigns. These may increase vaccination rates while avoiding the difficulties of administering
exemptions to a mandatory vaccine policy. Such measures include vaccine education initiatives, worksite
vaccination, covering vaccine costs, providing incentives, or offering time off for vaccinations and for
recovery from any side effects.
Author Information
April J. Anderson
Victoria L. Killion
Legislative Attorney
Legislative Attorney
Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff
to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of
Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of
information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role.
CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United
States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However,
as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the
permission of the copyright holder if you wish to copy or otherwise use copyrighted material.
LSB10573 · VERSION 1 · NEW