where: USA, Batman-fictionnal town of Blüdhaven (for sanity's sake, I choose to assume Blüdhaven's police (like Gotham's) works like the New York one.), nowadays
searched: Wikipedia (police, police procedure (which is about novels), nypd), google search (police procedure, ten-code, radio-code, police code, textbook police procedure), little_detail (*merge: police procedure,usa: government: law enforcement, gunshot wounds) and
ask_a_cop (current page and the two previous ones the day I searched) - plus various tv shows (probably wrong) and crime novels
In an indoor shooting leading to a murder witnessed by police officers, then one of the officers being hit (shot in the arm) and needing medical treatment, what's the police procedure?
The person murdered turns out to be Navy, so NCIS is going to take the case, and the shooter escapes.
Who else gets there on the scene? Back-up first, then EMT, or not that order at all? The shooting takes place at 8 - 8.30am - when does the NCIS team arrive, and who/what do they find (the residential building where the shooting happened will be shut down, police there, who's in charge, who interact with the NCIS team?)?
Or you can all tell me to go lay down and stop be anal over those pesky details I probably won't use the half of for a fanfiction in a fandom that takes the rules of all things reality and make them weep.