When you ask someone if they know
who did a certain thing, and they
give you answer that you know is
b.s. (bull shit)
Don't come in here with that who
shot john b.s.
Its a phase used to describe someone who is looking grimey or not their best.
Going out, look'n like who shot john?
Girl, you better comb your hair! I don't want you to go out of this house looking like who shot john.
Used by John Wayne in his last film that featured a young Ron Howard to describe another gunslinger's actions after he had a drink/got drunk. He used the term "who shot John" to describe the whiskey. It was in the scene where he was teaching Ron Howard how to shoot a pistol.
"You never know what he might do once he gets enough of that "who shot John" in him, Pilgrum!
illict liquor, moonshine(prohibition)
His ancestor was put in prison for selling who shot john.
A term used in a situation where a major event has occurred and you have no idea what's going on.
(Someone was stabbed at a party)
M: Yo did you see that?
J: No, man! Who shot john?