Patrol Case #4 - Buyer Beware - L.A. Noire wiki

Crime Scene - Nunn Bush Shoes

Examine the victim's jacket to find Lawaway Voucher.

Examine the ground near the street to find .32 Shell Casings.

Examine the trash can to find FN Browning handgun and Eagleson's Gun Store Location.

Interview the male eyewitness on the street.

Interview female witness inside the shoe store to discover Everett Gage.

Interview with Clovis Galletta:

Question #1 Eyewitness Account - Lie, Evidence = Layaway Voucher

Question #2 Possible Murder Suspect - Doubt

Question #3 Details of Shooting - Truth

Hartfields Jewelery Store:

Chase Edward Kalou

Aim your gun at Kalou until the reticule fills all the way up and you will fire a warning shot.  Note: You will fail if you shoot him.

Interrogation Room:

Question #1 Arguement with Gage: Lying, Evidence = Suspect Positively Identified

Question #2 Possible Religious Motive: Doubt

At the end of this case you will get the Police Academy Achievement for completing all cases on the Patrol Desk.