Visible crew/equipment: When the detectives are executing a search of Daniel's home, Benson is talking to his fiance. As she moves in front of the television, the reflection in the TV shows a crew member's legs moving alongside her. (00:25:10)
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)
Continuity mistake: Dr. Huang and Stabler are in the interrogation room with Joe when Joe starts telling him about the voices in his head. The boy is screaming for the voices to stop when Huang comes forward to comfort him. He takes his hand down from his ears, but in the next shot they're up near his head again. (00:18:25)
Visible crew/equipment: Stabler and Benson are with Christina in the interrogation room. Christina stands up to look out the window. Shortly after, she walks away from Stabler towards the foreground camera. As she does this, an overhead microphone is briefly visible in the mirror on the left. (00:35:55)
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.
Revealing mistake: After M.E. Warner tells Fin and Munch the boy was smothered to death, you can see the foot of the "dead body" twitch or move.
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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