A free man of color (1997)

Benjamin January, a free Black physician and musician in 1833 New Orleans, becomes entangled in a murder investigation while earning his living. Hambly makes racial status, access to employment and the danger of being disbelieved shape what he can investigate. Particularly strong if you want the setting to determine vulnerability as well as clothing and streets. The city’s social categories matter throughout; the mystery does not grant its detective modern freedom of movement.