Mid 1950's era Chicago Police car.

Mid 1950's era Chicago Police car., a photo by Eddie from Chicago on Flickr.

I took this photo of a photo a few years ago, during an August 2008 visit to Chicago's Navy Pier.

Inside one of the main hallways at Navy Pier, was a photo display honoring local Chicago area law enforcement.

This vintage black and white photo fom the mid 1950's era, shows how Chicago Police Department patrol cars were once black and white, and that the Chicago police officer's hats did not have the famous checker band on them just yet. The checker hat band would appear during the 1960's, and has remained a part of the Chicago Police Department uniform today.