Mackenzie Fierceton was championed as a former foster youth who had overcome an abusive childhood and won a prestigious Rhodes Scholarship. Then the University of Pennsylvania accused her of lying.

Rachel Aviv:

In the winter of her sophomore year of high school, Mackenzie Morrison sat in her bedroom closet and began a new diary. Using her phone to light the pages, she listed the “pros of telling”: “no more physical/emotional attacks,” “I get out of this dangerous house,” “the truth is finally out, I don’t have to lie or cover things up.” Under “cons of telling,” she wrote, “damaging mom’s life,” “could go into foster care,” “basically I would probably lose everything.” After she finished, she loosened the screws of a vent panel on the wall outside her closet and slipped the notebook behind it.

Mackenzie went to Whitfield, a private prep school in St. Louis, where the school’s wellness director, Ginny Fendell, called her the “queen of compartmentalization.” She got A’s, served in student government, played varsity soccer, managed the field-hockey team, and volunteered for the Special Olympics. She was five feet ten with long curly blond hair—“the picture of Americana,” as one friend described her. Mackenzie’s parents had separated when she was six, and Mackenzie lived with her mother, Carrie Morrison, the director of breast imaging and mammography at St. Luke’s Hospital, in Chesterfield, a wealthy suburb of St. Louis. They liked to imagine themselves as the Gilmore Girls: the single mother and her precocious daughter, so close they were nearly fused. But Mackenzie’s friends and teachers noticed that in her mother’s presence Mackenzie physically recoiled. Lisa Smith, the mother of one of Mackenzie’s best friends at Whitfield, said that her daughter once asked why Mackenzie was always injured: “My daughter kind of looked at me funny, and I looked back at her and said, ‘What are you trying to say?’ ”

When Fendell asked Mackenzie about her bruises, Mackenzie offered vague comments about being clumsy. Fendell told her that, if she couldn’t talk about why she was injured, she should write it down. “I don’t ever want to cause her any pain or anything, which is why I’ll probably end up burning this,” Mackenzie wrote in the journal. “I wish that I had the courage to tell someone. Or even to write everything down in here. Because if I’m being honest, there are things that I’m too ashamed to even speak of.”