## Facts

- California voters approved Proposition 13 in June 1978, adding article XIII A to the California Constitution.
- Article XIII A capped ad valorem property taxes at 1% of “full cash value,” generally rolled assessments back to 1975–76 levels, and limited annual assessment increases to 2% until a change in ownership or new construction.
- The measure also imposed supermajority vote requirements for specified state and local tax increases.
- School districts, counties, and cities filed consolidated original mandate proceedings challenging the measure’s validity on multiple constitutional grounds.
- Respondents included the State Board of Equalization, local tax officials, and the Attorney General on behalf of the state.

## Issues

1. Whether article XIII A constituted an impermissible constitutional “revision” rather than a permissible initiative “amendment.”
2. Whether the initiative violated the single-subject (one subject and purpose) requirement applicable to ballot measures.
3. Whether article XIII A was facially invalid due to vagueness/uncertainty, denial of equal protection or uniform taxation, or impairment of contracts and existing fiscal obligations.

## Decision

- The court denied the petitions and upheld article XIII A as constitutional on its face.
- The court held Proposition 13 was an amendment, not a revision, because it did not substantially alter the basic governmental framework despite its major fiscal effects.
- The court found the initiative satisfied the single-subject rule because its provisions were reasonably germane to a common purpose of limiting property taxation and related fiscal restraints.
- The court rejected facial challenges based on vagueness, equal protection, and impairment of contracts, while recognizing that more specific as-applied disputes could arise later.
- Chief Justice Bird concurred in part and dissented in part, expressing greater concern that the measure’s breadth and structural fiscal consequences pushed it toward a revision.

## Legal Principles

- The initiative power permits constitutional amendments but not constitutional revisions; a revision is assessed by both quantitative scope (wholesale constitutional change) and qualitative effect (alteration of fundamental constitutional structure).
- A measure satisfies the single-subject requirement when its provisions are reasonably germane to a common theme or purpose.
- Courts generally construe initiatives to preserve validity when a reasonable, harmonizing interpretation is available.
- Differential tax treatment created by acquisition-value assessment is reviewed under rational basis scrutiny for equal protection purposes and may be sustained if rationally related to legitimate governmental objectives.
- Broad facial attacks based on contract impairment and fiscal disruption may be rejected where the measure can be interpreted to preserve authority to meet voter-approved indebtedness, leaving concrete impairments for as-applied litigation.

## Conclusion

The California Supreme Court upheld Proposition 13 as a valid initiative amendment, concluding it did not amount to a prohibited constitutional revision, satisfied the single-subject rule, and was not facially unconstitutional on theories of vagueness, equal protection, or contract impairment.


Amador Valley Joint Union High Sch. Dist. v. State Bd. of Equalization, 22 Cal. 3d 208, 583 P.2d 1281 (Cal. 1978)