In April, 22-year-old Nushawn Williams, the precedent-setting PWA accused in 1997 of exposing a baker’s dozen to HIV in upstate New York, was sentenced to four to 12 years behind bars after his lawyers struck a plea bargain in the Bronx and Chautaqua County. While prosecuters pushed to lock him up and lose the key, they couldn’t wrangle a tougher sentence because only two of Williams’ women were willing to testify. But that doesn’t mean the nation’s most reviled PWA, who has been diagnosed as schizophrenic, is out of the woods yet: “If other people do come forward, we can prosecute,” said Chautaqua’s assistant district attorney, William Coughlin. “The door is still open.” But unless they step up to the stand soon, they have no case: The statute of limitations will run out in 2002.