By 1857, the New York City police department had a gallery where daguerreotypes of criminals were displayed. The Pinkerton National Detective Agency began using these on wanted posters in the United States. By the 1870s the agency had amassed the largest collection of mug shots in the U.S. In 1888, Alphonse Bertillon invented the modern mug shot featuring full face and profile views, standardizing the lighting and angles. This system was soon adopted throughout Europe, and in the United States and Russia. These examples from the 1920s may even appear as photos from a party or gathering to some, but they're actually real police mug shots. Continue reading for more.