Your BF would know, and if he says he doesn't know then he is lying to you. Should think twice before having any children with a guy who won't be honest with you and probably registered for life. Do a background check on him to see what else he ain't telling you.
Other possible penalties and/or consequences may include:
Lifetime requirement to register as a child sexual offender
Termination of parental rights
Supervised access to the child
Physical or actual loss and enjoyment of a child
Continual involvement with a child protective services agency
You can start looking for his name here: http://registryclassaction.com/
"New York, similarly to virtually every State in the union, maintains a Registry that lists the names of people who have supposedly abused or maltreated a child. Inclusion on the Registry is virtually automatic requiring only that the allegations satisfy a minimal “any credible evidence” standard. Although adding a name to the Registry is easily done the consequence of such inclusion can be economically devastating."
Serving 12 years? Must have been a heinous crime. My advice is to run not walk away from him