## Facts

- San Francisco health authorities reported multiple suspected bubonic plague deaths within a bounded area of Chinatown and sought authority to quarantine.
- The city enacted an ordinance authorizing the Board of Health to quarantine persons, houses, places, and districts to prevent spread of infectious disease.
- Officials established and enforced a cordon around a substantial portion of Chinatown, restricting residents’ movement out of the district.
- Evidence indicated the boundary lines were drawn to include predominantly Chinese-occupied premises while excluding nearby non-Chinese premises, sometimes closely tracing racial occupancy rather than disease indicators.
- In practice, enforcement burdened Chinese residents more heavily and allowed non-Chinese residents greater freedom of movement.
- Jew Ho, a Chinese resident and grocer within the quarantined area, alleged the quarantine halted his business and confined him without adequate medical justification for his location.
- Jew Ho sought a federal injunction, alleging the quarantine was arbitrary, unreasonable, and discriminatorily administered in violation of the Fourteenth Amendment.

## Issues

1. Whether the quarantine order, as drawn and enforced, exceeded permissible police power because it was unreasonable, arbitrary, and oppressive.
2. Whether the quarantine violated the Equal Protection Clause by discriminating against persons of Chinese descent in its design or administration.

## Decision

- The court held the quarantine invalid because it was unreasonable and arbitrarily overbroad as applied to the district.
- The court found the quarantine was administered in a racially discriminatory manner, burdening Chinese residents without a legitimate health-based justification.
- The court granted injunctive relief preventing enforcement of the quarantine in its existing form against Jew Ho (and effectively against similarly situated residents).

## Legal Principles

- Public health measures adopted under the police power must be reasonable and not arbitrary or oppressive.
- A quarantine must bear a real and substantial relation to preventing disease spread; broad confinement without sufficient factual basis can exceed lawful authority.
- Equal protection limits public health enforcement: racial discrimination in the drawing or administration of quarantine restrictions is unconstitutional.
- Courts may enjoin public health orders when the asserted health rationale operates as a pretext for unequal treatment.

## Conclusion

The court concluded that San Francisco’s Chinatown quarantine, though framed as a public health measure, lacked adequate justification in scope and was enforced along racial lines; it therefore exceeded legitimate police power and denied equal protection, warranting injunctive relief.


Jew Ho v. Williamson, 103 F. 10 (C.C.N.D. Cal. 1900)