Secrets (a.k.a. Apartment to Die For) - S2-E12
Visible crew/equipment: After the detectives bring in the fifteen adults from the swingers' club to the police station, Benson and Stabler bring in one of the men to the interrogation room. Right when they enter, an overhead microphone is visible in the top left-hand corner of the mirror behind them.
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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