A funeral is being held for a heroic member of the military (any branch of the military will do), the various intelligence services, or one of the law enforcement forces (particularly the NYPD). During the funeral, there is a salute using rifles, fired three times each. The camera lingers on one character who emotionally flinches in pain, fear, and distress at the sound of the guns.
This isn't merely the surprise one might feel at the report of the weapons when fired, this is an emotional reaction; a gut-punch to someone witnessing the funeral. This is Truth in Television; it is common for members of the deceased's family to flinch away in horror at the sound of the guns, especially if the deceased was killed in combat action. The flinch is used narratively to either a) highlight the difference between the civilians who are unused to gunfire as opposed to the honored dead and their stoic brothers in arms, who regularly endured it, and b) to add drama by alluding to the juxtaposition of honoring the sacrifice of the dead and their loved ones in a way that is traumatically similar to how they died. Alternatively, if done by a Shell-Shocked Veteran, they may be having a flashback.
On realism: Note that the technical term for the salute at military funerals is not a 21-gun salute, as is often said, but rather a three-volley salute. A 21-gun salute is performed with an artillery battery rather than riflemen, and in the United States only current or former presidents rate this honor. The actual number of riflemen varies from three to nineteen based on rank of the deceased.
- In The Departed, one of the ways we can tell that one character is a hard-hearted sociopath is that he's the only person who doesn't flinch at the sound of the guns at the police funeral.
- In Street Kings, this is used to show how Tom Ludlow is beginning to lose the cold hard veneer he had as the leader of a squad of vice cops after his partner is brutally murdered.
- Lt. Gordon flinches during the three-volley salute scene in The Dark Knight. Commissioner Loeb had been assassinated by the Joker and Gordon knew he would strike again, likely at the funeral, so his flinching is justified. Especially since Joker ends up trying to kill him during said salute a few seconds later.
- Parodied in Hot Shots! during Dead Meat's funeral. While his widow does the (understandable) flinching from hearing the salute, Admiral Benson all of a sudden thinks that the funeral is under attack and retaliates in kind with his sidearm and some grenades he carried just in case... while "protecting" the tearful, freaking-out widow.
- In the video for the Brad Paisley/Allison Krauss duet "Whiskey Lullaby", the man who drank himself to death is a war hero, and when he dies gets a funeral with full military honors, including a three-volley salute. The woman who drove him to drink himself to death by her infidelity visibly flinches when the rifles fire.
- Poet Walt Whitman, who attended the funeral of Abraham Lincoln, described his "painful reaction" to the sound of the rifle salute that took place at the deceased president's burial in one of his diaries.