Schey said the hiring audit at American Apparel had been "professionally done." By contrast, Schey has brought more than 100 damage claims against the immigration agency on behalf of American citizens who said they were illegally arrested last year in Los Angeles in an immigration raid at a different company, Micro Solutions Enterprises.

Immigration officials, who asked not to be identified because the case is continuing, said the fines to American Apparel so far were about $150,000.

Kelly A. Nantel, a spokeswoman for the immigration agency, said it had taken steps to limit negotiations with employers that in the past had resulted in steep reductions in fines the employers ultimately paid.

Rep. Brian P. Bilbray, R-Calif., who heads an immigration caucus in the House, said the amount of the fines was crucial.

"If this is a truly conscientious effort to get tough with employers to say the days are over of profiteering with illegal immigrants, that's fine," said Bilbray, who opposes any effort to give legal status to illegal immigrants. "But if the fine will be so low that it's just part of doing business, there's no deterrent."

Angelica Salas, the executive director of the Coalition for Humane Immigrant Rights of Los Angeles, an advocacy group, said she welcomed the end to "showboat enforcement raids." But in the end, Salas said, "there is still enforcement of laws that are broken," adding, "The workers will still lose their jobs."