This hat was found near the entrance to an alley, which the killer ran out of after committing the crime. Evidently, it was thrown away by the killer.
9 seconds sound clip from the Knock on Any Door movie soundboard.
You can hear this line at 01:25:53.119 in the Blu-ray version of the movie.
Quote context
[...]
- Look at me, Romano, not at the jury. That trick won't work.
- Answer this one carefully. Do you wear a hat?
- Sometimes I do, sometimes I don't.
- That night? Come on, come on.
- I call the jury's attention to exhibit C, already admitted into evidence.
- No.
- Well, would you please try it on? Let's see if it's becoming.
- Your honor. Your honor, may I take a look at the state's exhibit C?
- Proceed.
[...]