Last year, banks came under fire for using so-called robo-signers to process thousands of foreclosures a month without properly reviewing borrowers' paperwork. Now it appears that banks may have used robo-signers in creating mortgage deals as well. The government recently sued 17 banks over $200 billion worth of ill-fated mortgage bonds that were sold to Fannie Mae and Freddie Mac. According to the suits, the loans included in the deals had lower credit scores and down payments on average than the banks claimed. How did that happen? Documents reveal that many of the individuals who signed off on the mortgage bonds never worked at the banks and were often approving dozens of deals and thousands of loans for numerous banks at the same time. "Signing off on these loans should have been a meaningful function," says Joel Laitman, a lawyer who is representing investors in the soured deals. As with so much else on Wall Street at the time, there was less than meets the eye.