You don't know?
3 seconds sound clip from the Juice (1992) movie soundboard.
You can hear this line at 01:14:30 in the Blu-ray version of the movie.
Quote context
[...]
- Hell no, I ain't tellin' no police.
- You're mixed up in it, aren't you?
- I didn't kill him, if that's what you're thinkin'.
- Well, what are you gonna do about it?
- Excuse me? I thought he was your best friend.
[...]