Yeah the truth is most civilian's don't know Monday is used as a slur. Monday = term used within the police brotherhood to describe black people.
It's something you only hear around police... or retired police... and bigoted officers are careful not to use it around other officers unless they're sure everyone shares their view of black people.
This officer thought nobody would understand what he was saying because most people don't know what it means. Black people, including Crawford, know all too well what it means.
On another note I wonder if "Monday Night Football" will have to change it's name....
How about "Football on the Night the day after Sunday?"