when people say smoking gun in a sentence like if they're trying to solve a crime what are they talking about

Answer 1

they are talking about evidence and who might be in possession of "the smoking gun"

Answer 2

Generally speaking a "smoking gun" is irrefutable evidence or facts that make or break an argument ie finding finger prints on the murder weapon and matching them to the murderer. That is a smoking gun.

Answer 3

hi
smoking gun or red handed both mean cought in the scene . means they didnt have to find out about the responcible person coz they caught him while comitting his crime .
good luck