Thomas Jane's background story is similar to the role he played in the Punisher where after the death of his family (minus his wife) he starts drinking and contemplates on committing suicide.
This is the second time Thomas Jane has played a character named Carter, 1st time being Carter Blake in Deep Blue Sea.
The deputy is carrying a long-barreled Colt Python. Any deputy in their right mind would quickly trade that out for a shorter barreled pistol as the long barrel jams into the seat of the patrol car. Even a 6" barrel is uncomfortable to wear in a patrol car with a high ride duty holster let alone the one used for this film.