if some one was to acuse you of molesting her or him, 20 years ago (knowing that this person is trying to black mail you) and now he or she is threatening to report it to the police what would be the right way to handle the situation???
I would not respond to it at all. If 20 years have passed, it is likely any statute of limitations has passed on the civil case and the evidence would be very weak to pursue a criminal case. Do not discuss it and do not comment on it.