Skip to content
Home » COVID-19 vaccines employer mandates – legal basics for and against

COVID-19 vaccines employer mandates – legal basics for and against

This article about COVID-19 vaccines employer mandates was written by Dorit Rubinstein Reiss, Professor of Law at the University of California Hastings College of the Law (San Francisco, CA), who is a frequent contributor to this and many other blogs, providing in-depth, and intellectually stimulating, articles about vaccines, medical issues, social policy, and the law.

Professor Reiss writes extensively in law journals about the social and legal policies of vaccination. Additionally, Reiss is also a member of the Parent Advisory Board of Voices for Vaccines, a parent-led organization that supports and advocates for on-time vaccination and the reduction of vaccine-preventable disease. She is also a member of the Vaccines Working Group on Ethics and Policy.

The goal of this post is to give a short overview of the law surrounding employer mandates for COVID-19 vaccines. Two caveats. First, this post is not taking a position on whether a mandate is a good or bad idea for a specific employer: it is just setting out the law. Second, this post is focused on employers choosing to require vaccines, not states.

As preliminary comments, I want to remind readers that we do not actually know whether COVID-19 vaccines will dramatically reduce transmission. We know they are very effective at protecting recipients (and very safe), and we have reasonable grounds to expect they will reduce transmission somewhat, but we do not yet know to what extent. 

A workplace or employer mandate is, in part, justified by protecting the workforce – employers are expected, sometimes required, to minimize risks to their workers, and may be liable for work-related harms through workers’ compensation, but mandates are often justified by the protection of others – in this case, co-workers and customers – and if the vaccines do not reduce transmission, there is less justification.

We also do not yet know how long the COVID-19 vaccines’ immunity will last, and whether there are very rare side effects that have not yet been discovered. So this discussion has some uncertainty built-in. That uncertainty, however, would not directly change much of the legal framework described below.

COVID-19 vaccines employer mandates

Employer mandates for COVID-19 vaccines – starting point

The starting point is that employment in most states in the United States is at will. That means that unless the employment contract says otherwise, employers can fire employees for any reason, with few limits (see below).  Your employer can fire you because he or she does not like what you said on social media, does not like your hygiene habits, or the way you do your job.

That means that employers can also fire employees who do not want to get vaccinated. Employers can offer a different framework in the employment contract – for example, agree on a specific time during which an employee cannot be fired except for specific reasons, or agree to limit the reasons.  Some positions have tenure, which limits firing. But without such a contract, an employer has the freedom to terminate employment.

Further, employers have the ability to set out the rules of the workplace, including rules aimed to protect the health and safety of employees and customers. Employer mandates for COVID-19 vaccines are such a health and safety rule – it can protect employees and customers by reducing the risk of transmission of dangerous diseases on the premises. 

Vaccine mandates are not new and have been upheld in the past, absent a valid reason to overturn them. Past vaccine mandates included influenza mandates in healthcare settings and hepatitis A vaccines for restaurants

Important caveats

There are four caveats to keep in mind, however, that can limit the ability of employers to require covid-19 vaccines.

EUA and Mandates

First, the current COVID-19 vaccines, Pfizer and Moderna, are authorized under an emergency use authorization (EUA), not approved through the regular FDA process. There is legal uncertainty as to whether it is possible to mandate a vaccine under a EUA. I have initially set up the uncertainty here, explaining that the language in the law is unclear, and there are indications for and against allowing a mandate. 

My thinking has somewhat evolved since, and I am more inclined to think that for employers, at least, it is probably legal to require a vaccine under a EUA – or at least, such an employer would have a good argument in court, though it’s unclear which way a court will decide.

Four things support an employer mandating vaccines, in my view.

  1. The law does not address employers at all. It speaks to vaccine recipients, administrators, and the secretary, but does not directly impose anything on employers. In a reality in which employers normally would be able to impose a vaccine requirement, reading a prohibition into a law that doesn’t explicitly contain one is a big step.
  2. The law does mention that there can be consequences to removal.
  3. In guidance to employers, the Equal Employment Opportunities Commission (EEOC) did not suggest a EUA is a barrier to a mandate. 
  4. Finally, we know that quite a few employers have mandated testing – and many of those tests were only authorized under a EUA, creating a precedent for mandating something under a EUA.

The best argument to counter this would be to view the vaccine under a EUA as experimental, and concluding that you cannot mandate an experimental vaccine.

There is no jurisprudence directly on this point since there has never been a vaccine provided for general use under a EUA – the only previously EUA for a vaccine was for anthrax for the military only

In my assessment, an employer mandating a vaccine is taking a risk of litigation on this issue, but has a reasonable chance of success in such litigation, though there is also a chance of losing.

Collective Bargaining and Mandates

Another potential limit on an employer’s ability to mandate vaccines may come from collective bargaining. If the workforce is unionized, the collective bargaining agreement may require negotiating with the union before requiring a vaccine. Unions may or may not support a mandate.

This will be a case-by-case issue, depending on what specifically the collective bargaining agreement says, and what the union’s position is. In at least one case, a court upheld an arbitrator’s ruling that a vaccine mandate could not be imposed without a collective bargaining agreement

Unions opposing mandates in a case like this may not be anti-vaccine but may be acting to preserve their powers vis-à-vis management. But it is a potential limitation to COVID-19 vaccines employer mandates.

Americans with Disabilities Act and Mandates

The Americans with Disabilities Act (ADA) was created to protect the right of people with disabilities to access a variety of things, including workplaces. For the purpose of this discussion, the ADA requires employers with over 15 workers, in some circumstances, to provide reasonable accommodations to workers with medical conditions that make vaccines especially dangerous.

A vaccine contraindication would be a disability under the act, and the employer would have to provide accommodation unless it’s an undue hardship, which is a fairly high bar in this context, requiring showing a significant difficulty or expense. 

Accommodation, however, would not necessarily mean that the employee gets to access the workplace in exactly the same way as everybody else, or gets to set the term. The employer can create an accommodation that protects the medically exempt worker and others, for example, requiring that employers who cannot be vaccinated wear extra personal protective equipment (PPE), provide for social distancing between them and others, if possible, or if working remotely is an option, prioritizing such employees for such work. The EEOC provides more details. 

The balance is between not forcing the medically exempt individual – someone who cannot protect him or herself because of something beyond their control, a medical issue – to take a risk much higher than others by vaccinating, and protecting that person and others from Covid-19, in the absence of a vaccine.

Religion and Mandates

Most of the discussion so far applies to public and private employers alike. One area where there may be a difference is in relation to religion. Public employers are subject to constitutional limits, and private employers are not: you do not have constitutional rights against another private person, only against the government.

Public employers are subject, among other things, to the first amendment. Under our current jurisprudence, a government body does not need to give a religious exemption from a generally applicable law that does not target religion. However, with a change of personnel in the Supreme Court, we have a majority of justices that signaled, already, that they give substantial weight to religious freedom, and that jurisprudence may change. 

At some point, therefore, public employers may have to give a religious exemption from a mandate beyond what private employers have to.

Private employers with over 15 workers are subject to Title VII of the Civil Rights Act of 1964, which prohibits discrimination in the workplace based on “race, color, religion, sex and national origin.” 

For the purposes of COVID-19 vaccines employer mandates, the operational meaning is that if an employee has a sincere religious objection to vaccines, an employer has to provide a reasonable accommodation unless it’s an undue burden. I addressed this before, and the EEOC goes into details about it,
 but here is the essence of what you need to know, structured under the three parts of sincere religious beliefs, reasonable accommodation, and undue burden.

  1. Challenging a claim of sincere religious belief is full of pitfalls. An employer cannot require, for example, that an employee bring a letter from a priest, since that discriminates in favor of organized religion, or try to assess the reasonableness of the belief. An employer can, however, require an employee to write an explanation of their belief, and query the employee about that – but here, too, an employer needs to be careful. The focus is on personal belief and its sincerity. It needs to be religious in nature, and sincere. That does not require believing in a God, but it does mean that the belief has to be about fundamental questions and part of a system of belief. “I think vaccines are dangerous” won’t cut it, even if the employee cites one or two verses.
  2. The reasonable accommodation, again, does not have to be what the employee would prefer. In essence, courts are looking to whether the employer made a good faith effort to allow the employee to work in spite of the limits the belief imposes. 
  3. The undue burden here means something different than in the disability context, requiring an accommodation only if it’s less than a minimal cost.

This is a lower bar than for the ADA. In our article, Prof. Dubal and I argued that in the case of influenza mandate, the risks of influenza are more than minimal, and absolve an employer from giving a religious exemption. Depending on the circumstances, such an argument may well be made for Covid-19 too. 


Employers need to consider their liability in two opposite contexts here. First, if an employer requires vaccines from employees, any adverse reactions to the vaccine, as a work requirement, will likely be covered by workers’ compensation. Ironically, this may put workers who are required to get the vaccine in a better position compensation-wise than others who may have been harmed by a rare side effect, since anyone else needs to go through the very un-generous Countermeasures Injury Compensation Program

I have argued elsewhere that we should move Covid-19 vaccines to the more generous National Vaccine Injury Compensation Program.  I still believe so. In the meantime, workers compensation can cover those with a workplace mandate, at least, in the unlikely case that something happens. It does mean the employer would be liable, which employers may not appreciate.

On the other side, employers should consider that employees who contract Covid-19 on the job may also turn to workers compensation for a workplace injury, and customers who contract Covid-19 on the employer’s premises may sue – which may incentivize a mandate.

Showing causation may be hard: it may not always be clear where a person contracted Covid-19, but the standard in both cases would require showing that there’s more than 50% likelihood that it was at the workplace, and in the right case, that could be doable. It might also be hard to convince a judge and jury if a customer sues, that not having a mandate, or not working to increase vaccination rates, is unreasonable. But employers need to be aware that litigation is possible with a mandate – or without it. 


Employers have broad leeway to require covid-19 vaccines, though there are some limits. They can impose requirements – and can set different consequences for them, from firing a non-compliant employee to imposing PPE requirements or distancing, or giving special rewards to employees who do vaccinate.

There are limits that apply to all vaccine mandates from collective bargaining, the ADA, and the Civil Rights Act of 1964. For COVID-19 vaccines, the fact that these are EUA vaccines creates legal uncertainty – but that can turn out either way.

Just as important as the “can” question is whether employers should mandate covid-19 vaccines. That is itself a complex issue and involves many, many aspects. But it’s not this article.

Dorit Rubinstein Reiss

Don’t miss each new article!

We don’t spam! Read our privacy policy for more info.

Liked it? Take a second to support Dorit Rubinstein Reiss on Patreon!
Become a patron at Patreon!