Vilken är faktiskt snickaren?

Nej. Jack Reacher dödar inte dem ... han är den bra killen.

Den person som begått morden är "Charlie" (Jai Courtney).

Se diagrammet Synopsis här :

We cut to a meeting in a dark area between a guy who's been following Reacher, and the actual shooter, whose name is Charlie. We also meet the boss, who is only known as "The Zec" (Werner Herzog). We learn that only one of the victims was intended, and the rest were shot to cover this up. The first goon is being hassled by Charlie and The Zec about his loyalty after they get into an argument, and The Zec reveals that he bit off his fingers at one point to survive frostbite and gangrene. He orders the goon to do the same to prove his loyalty, but he can't, so Charlie shoots him. Charlie asks The Zec what they should do about Reacher, to which he replies "what we always do."

Här är han fortfarande från filmen:

Skytten var Charlie spelad av Jai Courtney och han gjorde för att han var anställd till och det riktiga målet var en byggföretagets ägare, "de dåliga killarna" ville förvärva sitt företag och ville inte ha någon misstanke om sin död.

Från detta

So the big twist in Jack Reacher is essentially that the whole sniper routine was a setup to kill one specific individual, and the other victims were murdered as a distraction, so the police and media would focus exclusively on the killer—who was handed to them in a frame-up.