Find the layaway voucher in victim's left pocket.

Dig up tossed FN Browning handgun from nearby trash can.

Inspect the litter of .32 shell casings near body.

Turn the gun in hand until Phelps identifies the make of the weapon and a nearby shop that carries it.
Enter Nunn Bush Shoes to begin interrogation of Galetta.

| Destination / Actions | Info / Clues / Tips |
Eyewitness account: Lie

Tip: Generally speaking, you'd benefit more from extracting every single clue in the area before speaking to witnesses.
This being the first of many questioning processes in the game, it's hard to miss any questions with the game telling you exactly how to respond to Ms. Galetta's assertions. Either way, you can start picking up on small nuances in facial features to discern whether a witness or suspect is twisting the truth.
Evidence: Layaway voucher

Possible murder suspect: Doubt

Details of shooting: Truth

Head to Eagleson's Gun Store

Get information on Kalou.

Investigate Hartfield's Jewelry Store

| Destination / Actions | Info / Clues / Tips |

Do not actually shoot Kalou. Pull out your weapon and point it on Kalou's fleeing body until the circle fills completely. This is how you do warning shots.
| Destination / Actions | Info / Clues / Tips |
Argument with Gage:Lie

Present evidence: Suspect positively identified

Possible religious motive: Doubt