Question 1: Are there any shoulder/collarbone wounds that would not necessarily need surgery? A particular place where they can get shot and have this be true, but still leave the person in a sling? (The sling part is not 100% strictly necessary.)
She goes to the hospital, gets treated, has to give a statement to the police, etc.
Question 2: When is the earliest time at which the hospital would be allowed to let her leave? This is providing that A) She did not need surgery, B) The police are done questioning her, C) She's insisting that she wants to leave, and D) She has someone to drive her home.
I tried a number of different articles using Google (with the keywords "gunshot" "wound" "shoulder" and "surgery"), but the specifics of my subject were tricky: Most of what I found discussed how fatal shots to certain parts of the shoulder/collarbone would be, how quickly you had to treat them, lasting damage, etc., but no one really gave a clear definition of where the line between "needs surgery" and "doesn't need surgery" is.
As for the hospital conduct one, I tried "hospital policy" "maine" "discharge", but what little specifics I did find were geared more towards people who had been in the hospital for a while, as opposed to being admitted within twelve hours for emergency treatment (and having the police involved).