Why wasn't Jennings arreasted when his book came out?

In his own book, Obamas new "Safe Schools Czar" Richard Jennings says that when he was an openly gay teacher, students often told him that they were having with older men, but that he never reported it, even though he knew the law said he had to. He says that one 13 yr old boy told him he was having w a 30yr old man, and that it made him feel dirty, and Jennings said he 'taught him' that it only made him feel dirty because society taught him that gay was dirty, and this if he enjoyed it he should carry on and not think of it as dirty. As a teacher he was a mandatory reporter, so it was a crime for him not to tell. Why was he not prosecuted?????