Federal authorities, who have not charged the Zimmermans, will say only that the investigation is "ongoing." Yet the Zimmermans say they don't know what they could have done differently. Just weeks before the raid, an auditor told them their documents looked clean, although it turned out almost all were forged. And it wasn't until four months after the raid that the Social Security Administration notified them that some of their employees might be illegal. "Until we have retina scans, there is no way for the employer to tell you who exactly is standing in front of them," says Eileen Scofield, an immigrant attorney in Atlanta. "Employers still hold this vulnerability."
The Zimmermans know that all too well. Earlier this month, immigration trouble came to the farm again when authorities arrested four of the dairy's new workers at a local Wal-Mart on charges that they, too, were in the country illegally. Mike's daughter Jenny went through the work documents for each of the arrested men, reviewing color copies of their identification papers. Mike had already asked the Border Patrol to examine the documents. He says the agency refused. What else could the Zimmermans do? Jenny shook her head. "They looked real to me."