Well, it's there, next to the salt.
3 seconds sound clip from the After the Thin Man (1936) movie soundboard.
You can hear this line at 01:10:32 in the DVD version of the movie.
Quote context
[...]
- But you don't really think she did it?
- No.
- You're not saying that just to make me happy, are you? You really mean it?
- No.
- Well, it's there, next to the salt.
- Of course you're right. She didn't do it. She couldn't have done it.
- I don't think I'd kill you if you ran off with another woman.
[...]