That woman, the real Yvonne Carrasco, has lived her entire life in rural Tulare County where she lives in a one-room shed-like building in the back yard of her boyfriend's mother's home

Carrasco doesn't know whose unpaid doctor bill cost her a chance at receiving public assistance for housing, because Naranjo is just one of at least four people who have used her identity.

As she sits on one of two beds in the cramped room that she shares with her boyfriend and two of her three children, Carrasco does know that she's never been to Reno, Nev., where a $411 unpaid podiatry bill apparently ruined her family's chance of moving to more spacious quarters earlier this year.

When her three-year wait for public housing assistance was finally up, Carrasco submitted applications to four places and failed to get into any of them. By the time she realized the podiatry bill was the hold-up, it was too late. Her 60 days to use the public assistance had passed.

"I want my own place so bad, I'd make sure to pay my rent, my bills," she says, shrugging. "They probably figured I was a high credit risk and wouldn't pay the rent."

A study released last year by the University of California's Center for the Study of Urban Poverty found that more than three-quarters of the nation's 117,000 day laborers are undocumented. However, that's only a small fraction of the nation's estimated 12 million undocumented immigrants.

In order to get around their lack of documentation, many unauthorized workers will start their own self-employed business or purchase a Social Security number.

In Carrasco's case, an entire identity was stolen. That was also the case in Utah when immigration agents arrested 145 people last December at a Hyrum meat-packing plant as part of an identity theft investigation that netted 1,282 arrests in five states.

A different kind of theft

Virginia Kice, spokeswoman for U.S. Immigration and Customs Enforcement, says theft of entire identities is becoming increasingly common, and it's a new trend. Traditionally, document vendors simply have made up a Social Security number, which may or may not match an actual person.

The Social Security Administration did a database check in 2000 and discovered that about 132,000 Utahns had Social Security numbers that had been compromised, says Richard Hamp, Utah's assistant attorney general who prosecutes identity-theft cases.