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.
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)
Answer: I didn't see the show so I don't know the details. A general answer would be because a reckless endangerment charge is easier to prove "beyond a Reasonable Doubt" in court and get a conviction. This charge would not require the prosecutor to prove intent, which would be required for proving aggravated or simple assault. Also, if there were no visible injuries, it is difficult to show bodily injury. Just because the reckless endangerment charge was specifically mentioned, it does not necessarily mean there were not other charges filed. Police often make multiple charges, like lesser-included offenses, so that the defendant's act will fall under one of them if the legal requirements are not met for the others, if they are not sure of the best charge to make (the district attorney knows and can decide), or to have something to plea bargain with.
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