Character mistake: Capt. Cragen says that Columbine shooter Eric Harris shouts, "All jocks stand up" during the massacre, when, in fact, it was the other perpetrator, Dylan Klebold who stated this. (00:12:20)
Character mistake: When Casey is talking to Rebecca Balthus about Jennifer's defense, Balthus claims that Jennifer is innocent and intends to prove it. While she can present a defense, Balthus is not required to prove anything: the burden of proof lies solely on Casey; Jennifer possesses what is called the presumption of innocence, the basic principle that she is considered innocent until it's proven she's guilty.
Answer: It was a misconception about Jehovah's Witnesses beliefs. Only blood transfusions are discouraged in their beliefs, medically.