Williams pled guilty in 1998 to one count of statutory rape for sex with a minor, and two counts of reckless endangerment for knowingly having unprotected sex while infected with HIV. In court records, however, he contended that he did not knowingly infect anyone with HIV and claimed he did not remember being informed he was HIV positive in 1996.
He served two consecutive sentences of two to six years and was scheduled to be release this past April. But after a psychological review with health officials at the prison, he was deemed to still be a danger to society, and continued to be held behind bars under the state's Civil Confinement Law, which was enacted in 2007.
"Nushawn was really preying on young girls in this area, and he infected a lot them with HIV. That's a scary thing to think about him continuing to do if he gets out," Chautauqua County District Attorney David Foley told ABC News in an interview.
New York is one of 20 states with civil confinement laws, in which sex offenders deemed to still be a danger to society after their prison terms are finished can be held for the rest of their lives. Under New York's law, the offender is held in a state run psychiatric facility and the confinement is subject to yearly review.
On Monday, Grasso tried to have the civil confinement case thrown out, but was denied by State Supreme Court Judge Michael Michalski.
Grasso argued that Williams had finished serving time for the sexual offense -- statutory rape -- in 2004 and was serving time for reckless endangerment in 2007, when the Civil Confinement Law was passed. Reckless endangerment does not fall under the confinement law, Grasso maintained.
According to Grasso, the case represents something bigger than his client, and that civil confinement is an unfair and unjust law that lacks the proper transparency.
"I've read the law, and never see where it stops. When does a person complete their sentence, 105 and in the grave? That's the whole point, it never does stop," Grasso said.
"It's inherently not fair. The thing that really gets me is the lack of transparency. Who are these people who make the determination, which guy goes through this proceeding, and which guy does not?" he said.
Court records show the New York Attorney General's office argued in Monday's hearing that Williams' convictions qualify him as a sex offender, regardless of when the civil confinement law was enacted. They also argued he is still a threat to society, citing over 20 violations while serving his prison sentence, as well as Williams being diagnosed with substance abuse disorders, Psychopathy and Antisocial Personality Disorder.
A mental health evaluation of Williams conducted by the State Office of Mental Health also mentions that Williams allegedly informed an associate in prison that if he was released he would continue to intentionally infect women with HIV, however it does question the voracity of the allegation although it is "consistent" with Williams' past behavior.
"I don't think any of his records from state prison show he's been rehabilitated," District Attorney Foley said. "I certainly support the AG's decision to civilly confine him."
Williams' next opportunity to argue for release is Oct. 12, the date for his civil confinement hearing.
Grasso admits he has an uphill battle, fighting for a side that is hard pressed to garner any public sympathy.