Factual error: The way that the drug Scopolamine is described is not accurate. It does not render the victim "unable to resist instructions". It can produce "twilight sleep", delirium and euphoria, but does not give anyone complete control over another person as depicted in the episode.
Factual error: The cast is in the squad-room trying to ascertain the location of the Marine Corp unit. Finn's says there's 2 pilots and a "door gunner" per bird. The Bell AH-1 Cobra is a 2 man lite attack helicopter that has a tandem style seating system in which the Gunner sits in front of and below the pilot. There is no room for a side door let alone a door gunner, as in the picture they use. (00:12:50)
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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