Jennifer Banks (Sarah Hyland) is the villainess of "Hothouse", episode 10.12 of Law & Order: SVU (airdate January 13, 2009). She was a wealthy and intellectually gifted 14-year-old girl. She was a student at Morewood, a private school specifically for intellectually proficient students. She was the roommate and best friend of Elsa Lychkoff, who was found dead in the Hudson River in the beginning of the episode.
When first questioned by Detectives Olivia Benson and Elliot Stabler, Jennifer claimed that she and Elsa were close and insinuated that Elsa's abusive father Joseph was her murderer. But after security footage showed that Joseph was at a casino at the time of Elsa's murder, Benson and Stabler learned from Elsa's friend Danny Burke the true nature of her relationship to Elsa: they had grown to hate each other after Elsa refused to fail an exam so Jennifer could feel academically superior, having been pushed to be academically perfect by Morewood.
When questioned, Jennifer at first claimed that Danny was lying before admitting her hatred for Elsa while being interrogated with her mother Suzanne present. Ultimately, Jennifer had a psychotic breakdown and admitted to killing Elsa, having followed her to the ferry to talk to her. When Elsa insulted Jennifer and claimed she only got into Morewood because of her family's wealth, Jennifer snapped and bludgeoned Elsa to death before throwing her body in the river. When it was determined that the murder was committed in Hoboken, Jennifer was put on trial in New Jersey, with ADA Kendra Gill intending to give Jennifer a life sentence. During her trial, Jennifer had another breakdown and was put in lockup, where she revealed another secret to Benson: she had been abusing Provigil to stay awake to study, which she (like many Morewood students) had been persuaded to use by the school, even going as far as to tell them how to get a prescription. Jennifer went on to reveal how she'd been awake for six days by the time she'd attacked Elsa and how she had wanting to repair her friendship with her when she went to the ferry. M.E. Melinda Warner concluded that Jennifer's Provigil abuse had been the cause of her crime and Benson was able to convince Gill to offer Elsa a plea deal, which sentenced her to a seven year stay in a juvenile detention center.