There were a significant number of Colt Collection guns stolen and illegally traded by an employee of the CT State Library around 1980. When it was discovered it was big news because it was a trusted state employee and it took such a long time to uncover.
For example in the photo below, there's 2 experimental Colt guns listed as having been illegally traded, #8 & #10. There were many others too.
http://www.flickr.com/photos/ctarchives/5075295224/