Hypothesis:

She’s been murdered. Somewhere, her body lies in a field or behind a dumpster. A man, burly and demented, played with her until bored. He raped her, abused her, shot her in the chest with a .38 revolver, and left her beside a little-used road or buried beneath a few inches of dirt near a construction site. She was captured on her way home from school. A car, a 1978 Buick, pulled beside. It’s front right quarter panel was spotted with rust and bashed in. The window rolled down and a quiet voice, barely audible, asked a question. Joan stepped forward to hear and was caught, yanked through the driver’s side. The machine darted away, and Joan’s legs were briefly visible.

Refutation:

If she were murdered, why hasn’t it been mentioned on the news or in the paper? Why haven’t her parents come forward with tearful appeals, asking anyone to help find their daughter? Why haven’t the police been through the school, peppering the grounds with questions and accusations?

Who were her peers?  

Why don't they miss her?