This is earned during the story “A Slip of the Tongue”. It is not difficult to earn but can be missed if you don’t check everything. It involves inspecting 4 pink slips (vehicle certificates of title).
The first three will be handed to you during interviews from Cliff Harrison, Richard Coombs, and James Belasco. The fourth you find after you’ve cornered Steven Bigelow at 58 Industrial Street. They are in a box on his desk.