Allow the player to compose a sketch based on the different physical features, which could then be used to inquire about potential suspects matching the sketch.
For example, the player can purchase a new item, like a notepad, which enables them to select various elements such as build (muscular, skinny, etc.), height (short, average, etc.), hair type, hair color, and so on. With this, players can then approach NPCs and ask if they have seen someone resembling the sketch. If the player has accurately selected many physical details, and the NPC wants to cooperate, the responses from witnesses could be more precise, such as, "Yes, that looks like X, he's a coworker." Or even go around nearby bars/restaurants to ask the staff if they saw someone like them recently.