Roughly two dozen California tribes have disenrolled more than 2,500 Indians in the past decade on the basis of not having proper ancestry, according to estimates by Indian advocates and academics, reported The New York Times. More than 362,000 Indians reside in California, according to the 2010 census.

While inner-tribal turmoil has on occasion incited disenrollment, critics attribute the high rates of California's cast-off tribal members to gambling revenues. The state's 60-plus Indian casinos netted nearly $7 billion last year—more than any other state, according to the Indian Gaming Commission. Some small tribes that disseminate casinos profits pay members monthly checks upwards of $15,000. Many tribes also offer housing allowances and college scholarships.

Tribal governments universally defend their reasons for disenrolling members, claiming they are removing people with little tribal association, who likely joined to exploit the services, scholarships and monthly checks from casino profits. “You have people who want to be tribal members, where no one knows who they are or where they came from,” said Reggie Lewis, chairman of the Chukchansi Tribal Council, to The New York Times. “We are sworn to uphold the Constitution. And basically that’s what we try to do.”

But for people like Ruby Cordero, 87, an ousted Chukchansi, expert basket weaver and one of the few last native speakers of the Chukchansi language, disenrollment is the equivalent of robbery of her identity and culture. “She was born and raised on that property,” Nancy Dondero, Ruby’s great-niece, told the Times.

In October, Indian Country Today Media Network reported in "Bitter Fight to Determine Who Is an Indian Turns to DNA Testing" how many tribes have adopted a DNA-testing ordinance to determine tribal membership.