In "The Dishwasher," a Mexican folk song of the 1920s, an illegal immigrant tells how he pursued his dreams to California and found a harsh life washing dishes, mixing cement and picking tomatoes.

The tragicomic song, which appears in UC Irvine anthropologist Leo Chavez's new book about illegal immigrants in San Diego County, ends like this:

\o7 Goodby dream of my life, goodby movie stars, I am going back to my beloved homeland, much poorer than when I came.\f7

The historic and cultural roots of Mexican immigration to the United States evoked by this and other folk songs, or \o7 corridos,\f7 are among the central themes of "Shadowed Lives: Undocumented Immigrants in American Society," the first book by Chavez, a professor at UCI.

Chavez says he used songs about immigration and extensive interviews in order to let immigrants--the topic of voluminous discussion by experts, advocates and critics--tell their own stories in their own voices.

"The goal of the book is to personalize the immigrant experience beyond the cost-benefit analysis, beyond the politics," said Chavez, 40, a nationally known expert on immigration. "It is to introduce immigrants as human beings."

The book emphasizes case histories and personal anecdotes over academic jargon or sweeping conclusions, providing a relatively rare portrait of illegal immigrants, according to other academics. As the research process took Chavez deeper into the shadows of society where his subjects lived, it turned him into a vocal advocate for illegal immigrants and for more tolerant government policies.

Chavez said he wants "Shadowed Lives" to counter a growing current of anti-immigrant sentiment. He contends that illegal immigration has benefited American society by providing a low-wage foundation for prosperity.

"It's an appeal not to put the blame on immigrants for all the social and economic ills we are having," he said. "What I didn't realize is the extent to which the middle-class lifestyle I took for granted was supported by immigrants who are looked down on by our society.

"Some of the most vociferous opposition is (in San Diego), the most vocal anti-immigrant people in the country. People don't understand that San Diego is what it is because of immigrants who work to maintain the lifestyle that San Diegans enjoy."

This point of view invites controversy, particularly during an economic crisis when a growing number of political leaders at national, state and local levels are asking hard questions about the costs of and limits on immigration.