"Here's the way it works," he explained. "[They're] supposed to report reasonable suspicion of child sexual abuse. Sexual activity by an underage girl is reasonable suspicion . . . because she cannot legally consent. So therefore, any sexual activity she has is, by definition, without her consent. So, [the authorities] have to investigate that for suspicion that it's sexual abuse."
In my state, teachers are mandatory reporters, meaning child abuse would have to be reported to either Protective Services, law enforcement or both. Unless I'm reading this wrong, that's what "the authorities" are in this sentence: So, [the authorities] have to investigate that for suspicion that it's sexual abuse." If that's not what they're suggesting be done, then I'm sure you can correct me.
The primary "authorities" in a minor's life are their parents. If your "authorities" are hiding abuse (which includes denial of parental notification of abortion) from the minor's parents, your government "authorities" should be subject to litigation and criminal prosecution.