## Facts

- The City of Chehalis owned and operated a municipal water system supplying residents and some nonresidents.
- The city enacted Ordinance No. 653‑A directing that an approved fluoridating agent be added to the municipal water supply under state health rules and supervision.
- Arthur A. Kaul, a resident, voter, and taxpayer whose home was connected to the municipal system, sued to enjoin fluoridation.
- The trial court found that fluoride is poisonous at some levels but that adding fluoride ion at one part per million would not contaminate the water and the water would remain wholesome.
- The trial court also found fluoride at that concentration does not act on the water itself (unlike chlorine used to address bacteria) and is added solely for its effect on people who drink the water.
- The court found residents effectively lacked a practical alternative domestic water source.
- Kaul argued that requiring consumption of fluoridated water invaded constitutional liberty and exceeded the city’s police power, likening the measure to impermissible forms of compulsion.
- Kaul did not challenge the trial court’s findings of fact on appeal.

## Issues

1. Whether a municipality may, under its police power, require fluoridation of a public water supply to improve public health by reducing tooth decay.
2. Whether fluoridation of a municipal water supply unconstitutionally infringes individual liberty or due process by effectively compelling ingestion.

## Decision

- The Washington Supreme Court affirmed the dismissal of Kaul’s injunction action.
- The court held the ordinance was a valid exercise of municipal police power directed to public health.
- The court held fluoridation at the established concentration did not violate constitutional liberty or due process.
- The ordinance remained enforceable.

## Legal Principles

- Municipal public-health regulations enacted under the police power are presumed valid and will be sustained if reasonably related to public health, safety, morals, or general welfare and not arbitrary or unreasonable.
- Courts defer to legislative judgment on disputed scientific and policy matters when the regulation bears a reasonable health relation and the factual record supports its safety at the regulated level.
- Operation of a municipal utility in a proprietary capacity does not negate a city’s authority to set public-health-related conditions for the water supplied through legislative action.
- A generally applicable, non-discriminatory regulation of a municipal water supply to address a health concern does not constitute unconstitutional compulsion merely because residents will foreseeably consume the water.

## Conclusion

The court upheld Chehalis’s fluoridation ordinance, concluding that fluoridating the municipal water supply at one part per million was a reasonable, non-arbitrary public-health measure within the city’s police power and did not violate constitutional protections of liberty or due process.


Kaul v. City of Chehalis, 277 P.2d 352 (Wash. 1954)