Continuity mistake: When Stabler steps out to confront Tarzi, there is a long, brown brick wall to Tarzi's right. Tarzi then turns and runs across the street and is followed by Fin. Munch steps out and yells "halt!" There is another shot of Tarzi and he stops again. Right before he is tackled by Fin, behind him, to his right, is the same brick wall as before even though he crossed the street and ran down the block.
Continuity mistake: In the scene where Detective Munch visits the hospital room of a young comatose girl for the first time, the girl's left arm is alongside her body above the top sheet. As Munch approaches the bed, her arm is below the top sheet. When Munch visits the still-comatose girl a second time in the last scene of the episode, in the foreground as he is entering the room the girl's head is turned, facing her right. As he pauses to watch her, in the next shot she is now facing upright towards the ceiling. In this same shot, the purportedly still-comatose girl slightly moves her head and lips as if swallowing.
Continuity mistake: At the beginning of the episode, Alvin Maddox looks over the counter to discover the body. Her underwear is around her right ankle. Later, when Stabler is examining the body, the underwear has shifted to be around her left ankle.
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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