Monkeys can't speak so just picture the gestures

A bus crashes, and everyone onboard dies, the only survivor is a monkey.
A cop comes to interrogate the monkey..

Cop:
So what did you see?

Monkey:
places fingers to lips and sucks in

Cop:
So they were doing drugs?

Monkey:
nods yes

Cop:
So what else did you see?

Monkey:
cups hand up to lips and tilts head back

Cop:
So they were drinking too?

Monkey:
nods yes

Cop:
Did you see anything else?

Monkey:
strokes his penis

Cop:
So they were having sex too?

Monkey:
nods yes

Cop:
And what were you doing this whole time?

Monkey:
grabs imaginary steering wheel and looks over his shoulder...