i was thinking he was trying his best to keep the coke "in".
i haven't done coke myself but i've been around people who have. i can imagine the sniff is a kicker and keeping a straight face and controlling yourself may or may not be hard, i don't know. i mean, he felt he had just been busted so the natural thing would be to act as if he's not on coke, thus, being a lil drunk and sloppy would give you that idea.
or maybe he was just drunk