Character mistake: When Munch and Finn visit victim's apartment, Munch states that the glass in the broken window is tempered, The glass is not tempered but more likely laminated wire glass; due to he fact that the glass is still intact and the child had to use wire cutters to get out.
Character mistake: The fetus' blood type was AB and the mother had a known type of A. So Dr. Huang said the Father had to be type B which is not completely true. The father could also be type AB as long as he had a single chromosomal copy of the B allele, which any doctor would know. During meiosis only half your genetic DNA is passed on to the offspring.
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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