Why does Amy wear a cop uniform after she becomes sargeant but Terry Crews is also a sargeant but doesn't wear one and why is there no lieutenant in the 99th precinct? :
Why do detectives wear uniforms? - Quora
New NYPD chief wants to clean up cops' sloppy style
Detectives are banned from wearing denim and other casual clothing in Western Australia | Daily Mail Online
Cops and Robbers - Dallas Vintage Clothing & Costume Shop
Dressed for a Meeting, Ready for Mayhem - The New York Times
Baltimore police plainclothes units now in uniform, marked cars
NYPD head warns officers not to wear uniforms or department logos in public | Daily Mail Online
How to Become a Detective: A Guide to Police and PI Work