Cultural affiliation under NAGPRA could be established through multiple types of evidence — geographic association, biological evidence, archaeological and anthropological evidence, linguistic evidence, oral tradition, and other information.

The law was deliberately broad in its evidentiary standards, reflecting the recognition that Indigenous communities might have forms of knowledge about their own histories that Western science did not document or understand.

The Fallon Paiute-Shoshone Tribe had strong geographic reasons to claim the Spirit Cave Man as an ancestor.

The Spirit Cave site sits within what the Tribe considers its ancestral territory.

The Tribe had been the primary Native American community in the region around Spirit Cave for as far back as oral tradition and historical documentation could reach.