Factual error: The episode took a lot of liberties to further the plot when Amelia Albers was arrested by the Coast Guard in ADA Barba's office. While the story mentioned a real controversial military pamphlet on how victims should respond to a sexual assault, at the time the episode took place, the military was under a massive investigation over sexual assaults in Washington, was being widely criticized for lack of assault victim support, and had a bill being considered in Congress to make it easier for victims to report their attackers. There is no way any military prosecutor would have been given clearance to charge Amelia with adultery or fraternization while the men she was accused of sleeping with were arrested and already on trial for gang-raping her. Doing so would bring a lot of unwanted bad press and a possible congressional investigation on the Coast Guard that would almost certainly want to know why they are attempting to cover up a rape by charging the victim instead, especially when the rape victim was an admiral's daughter.
Factual error: When sergeant Benson is in the bathroom alone after it has been declared clear she looks at her phone to see a picture message from Lewis of the little girl he has tied up. She then texts him back saying "where are you" but at the top of the screen it says unknown as if the sender has blocked their number, so it would be physically impossible for sergeant Benson to reply to this message. (00:26:25)
Plot hole: M.E. Warner explains of Lewis and Benson "both their fingerprints are on the gun." Lewis burned his off in a particularly gruesome scene a few episodes earlier. (It was at the beginning of his arc). Only Benson's should be on her gun. (00:29:20)
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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