In the midst of a wave of infections, hospitalizations, and deaths attributable to the Delta variant and low vaccination rates in many parts of the country, many state and local governments, and private employers and businesses in the United States (‘US’) are turning to vaccination mandates. Like every other aspect of pandemic response, vaccine requirements and verification programs for Covid-19 have been highly politicized in the US. As some states announce new mandates or tighten existing ones, others are fighting against vaccination requirements, even going so far as to prohibit private businesses from requiring their patrons to show proof of vaccination.

Litigants opposed to vaccination are challenging private and public vaccination requirements in the courts, resulting in some early decisions that are largely supportive of vaccine mandates for Covid-19. Reasonable vaccination requirements that offer exemptions for individuals for whom vaccination is inconsistent with sincerely-held religious beliefs are very likely to withstand legal challenges. Laws that omit religious exemptions are on less firm ground and may be struck down by the courts, particularly in light of the Supreme Court’s recent signals that it is adopting a new position that is highly protective of religious liberty.

In the decades prior to the Covid-19 pandemic, the courts uniformly upheld reasonable vaccination requirements, even in the absence of a religious exemption. In doing so, they relied on a combination of precedents from the US Supreme Court, including Jacobson v Massachusetts (a 1905 decision upholding a law imposing a criminal fine on any adult who refused to comply with a local smallpox vaccination order on the grounds that laws may limit the bodily autonomy of individuals to secure the public’s health) and Employment Division v Smith (a 1990 decision upholding a law prohibiting use of illicit drugs, including a drug used by some Native Americans tribes as part of a religious sacrament, on the grounds that a generally applicable law may incidentally burden the exercise of religion so long as it has some reasonable basis).  Beginning in November 2020, when the replacement of Ruth Bader Ginsberg with Amy Coney Barrett changed the composition of the Supreme Court, both of these precedents were called into question. Multiple Justices expressed disdain for the very low standard of judicial review adopted in Jacobson, at least as applied to religious liberty challenges, and the majority found that secular exceptions to laws render them 'not generally applicable' such that religious exceptions must be available on equal or better terms. The latter approach has been referred to as demanding 'most favored nation status' for religious exercise.

The lower courts are now grappling with the impact of the new majority’s emerging shift on public health authority and religious liberty for Covid-19 vaccination requirements. Individuals opposed to vaccination are raising two distinct types of individual rights: bodily autonomy and religious liberty. Arguments grounded in bodily autonomy have (so far) been rejected by federal judges in Klaassen v Trustees of Indiana University and Dahl v Trustees of Western Michigan University. Both cases have reaffirmed Jacobson as a valid precedent for subjecting vaccination requirements challenged on bodily autonomy grounds to rational basis review. In Dahl, however, a federal district judge has signaled that he interprets recent Supreme Court decisions to direct the courts to strictly scrutinize vaccination requirements that allow some exemptions (for example, those granted based on a physician’s assessment that vaccination is medically inappropriate for an individual due to their health conditions) while imposing limits on people who assert they have chosen not to be vaccinated for religious reasons.

Klaassen and Dahl have only reached a preliminary stage in litigation, without any final decision on the merits. Both cases involve public university vaccination requirements. In Klaassen, the Court of Appeals for the Seventh Circuit declined to grant a preliminary injunction blocking the university from implementing its vaccination requirements for students. The plaintiffs asked the Supreme Court to intervene, but their request was denied, a move that many interpret to mean Jacobson is safe. In Dahl, a federal district court judge declined to grant a temporary restraining order (TRO) to an employee who is arguing that she should be exempt based on infection-acquired immunity, but did grant a TRO to student-athletes who were told they could not participate in inter-collegiate sports unless they provide proof of vaccination, even though their religious objections were sufficient to allow them to attend classes and keep their athletic scholarships.

Dahl and Klaassen will continue to make their way through the litigation process, along with other cases, such as Does 1-6 v Mills (in which a judge denied an initial request for a TRO from health care workers challenging Maine’s law requiring them to be vaccinated for Covid-19 as a condition of employment without allowing any religious exemptions, but without any assessment of their likelihood of success on the merits). Health care workers are also poised to challenge a similar law in New York requiring them to be vaccinated without offering religious exemptions. And additional Government actors may decide to adopt new vaccination requirements without religious exemptions.

Whether the Supreme Court will ultimately wade into these disputes over vaccination requirements that do not allow for religious exemptions—and how it might adjudicate them if it does so—remain to be seen. Many analysts reading the tea leaves of the Supreme Court’s rulings on religious liberty challenges to other laws (mostly, but not exclusively, involving Covid-19 restrictions) expect the Court to impose a new constitutional requirement that vaccination laws offering any exemptions whatsoever must also offer religious exemptions. There may be a narrow path for the new majority to uphold vaccination requirements in the absence of religious exemptions, however, even as it pursues its religious liberty agenda in other cases. A 2021 district court decision, M A v Rockland County Department of Health (upholding a 2019 public health emergency order responding to a measles outbreak in New York) offers the best available approach to threading this needle. In M A, the district court applied the Supreme Court’s recent rulings expanding religious liberty but found that medical exemptions do not render a vaccination requirement 'not generally applicable.' The district court reasoned that medical exemptions are integral to vaccination mandates in a way that exceptions to gathering bans blocked by the Supreme Court were not. Both the vaccination mandate and the provision for medical exemptions are aimed at protecting individuals who cannot safely be vaccinated by securing community immunity.