In the case of Whitney v. Hay, 1900, the United States Supreme Court addressed a dispute over land ownership in California. The plaintiff, Whitney, claimed that he had purchased a parcel of land from one Mr. Pioche and subsequently paid all taxes on it for several years before discovering that defendant Hay also held title to the same property through an earlier purchase from Pioche's estate administrators. The lower court ruled in favor of Hay based on his prior claim and because there was no evidence showing any fraud or mistake involved in his acquisition process. Whitney appealed this decision to the Supreme Court arguing that since he had been paying taxes on the property without knowledge of any competing claims, he should be recognized as its rightful owner under principles of equity law which aim at preventing unjust enrichment at another’s expense. The Supreme Court disagreed with Whitney's argument stating that tax payments alone do not establish legal ownership rights especially when there is no proof indicating fraudulent intent by other claimants (Hay). Therefore, despite having paid taxes for several years unknowingly while someone else held valid title deeds; such actions did not automatically confer upon him (Whitney) exclusive rights over disputed lands.

The dissenting opinion in the case of WHITNEY v. HAY, 1900 was not recorded or is unavailable. The Supreme Court's decision was unanimous with no noted dissents.