## Facts

- Massachusetts authorized local boards of health to require adult vaccination when necessary for public health or safety, with refusal punishable by a $5 fine.
- During a 1902 smallpox outbreak, the Cambridge Board of Health ordered vaccination or revaccination for city inhabitants not successfully vaccinated since March 1, 1897.
- Henning Jacobson, a Cambridge resident and pastor, refused vaccination, alleging prior vaccination caused him severe suffering and that he and his son had adverse reactions suggesting susceptibility.
- Jacobson was prosecuted, convicted in a Massachusetts trial court, and fined $5.
- The Supreme Judicial Court of Massachusetts affirmed the conviction; Jacobson sought review in the U.S. Supreme Court, claiming a Fourteenth Amendment violation.

## Issues

1. Whether a state compulsory vaccination law, as applied, violates the Fourteenth Amendment’s protection of liberty by being unreasonable, arbitrary, or oppressive.
2. What constitutional limits constrain a state’s police power to enact public health measures during an epidemic.
3. Whether exempting certain children on medical grounds denies equal protection to adults subject to the vaccination requirement.

## Decision

- The Supreme Court affirmed the conviction and upheld the compulsory vaccination regime.
- The Court held that compulsory vaccination for smallpox fell within the state’s police power to protect public health and safety.
- The Court concluded the law was not shown to be arbitrary or oppressive as applied to Jacobson, given the limited penalty and the lack of proof that he was medically unfit for vaccination.
- The Court rejected the equal protection challenge based on limited child exemptions supported by health-related reasons.
- Justices Brewer and Peckham dissented (Brewer without opinion; Peckham objecting to the breadth of deference to state action).

## Legal Principles

- The Fourteenth Amendment does not secure an absolute right to be free from restraint; personal liberty may be limited by reasonable regulations protecting others from serious harm.
- States may enact health measures under their police power when reasonably related to protecting public health and safety, including during an epidemic.
- Courts generally defer to legislative judgment on public health policy unless the measure is a plain, palpable invasion of constitutional rights or is arbitrary and oppressive.
- A modest fine for noncompliance may support a finding that a public health regulation is proportionate, especially where the law does not mandate forcible vaccination.
- As-applied limits may exist where an individual can show they are not a fit subject for vaccination; absent such proof, enforcement is typically sustained.
- Differential treatment, such as medically justified exemptions for children, does not violate equal protection if the law applies equally to all adults in like condition.

## Conclusion

Jacobson sustained a state’s authority to require vaccination during a smallpox outbreak, holding that the Fourteenth Amendment permits reasonable, non-arbitrary public health regulations under state police power, while leaving open the possibility of relief in exceptional cases of medically inappropriate application.


Jacobson v. Massachusetts, 197 U.S. 11 (1905)