A police collection of photographs of criminals; mug shot
Any group or collection of unsavory persons; den of thieves: The new building commission is a plain rogues' gallery(1859+)
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with rogues gallery
A police collection of pictures of criminals and suspects kept for identification purposes. For example, The detective went through the entire rogues' gallery but couldn't find a match with the suspect.