to protect and serve.

Image from uspsstamps.com

Within the postal system exists one of the nation's oldest law-enforcement agencies, dating back to the late 18th century when mail theft was punishable by death.

This agency is known as the United States Postal Inspection Service, or USPIS, and it protects the public by enforcing postal laws, handling everything from mail scams to the stuff of primetime television dramas. 

The agency's achievements varied in nature, from the 1934 transfer of America's $15.5 billion gold reserve from New York to Fort Knox (a trip that took Post Office inspectors several years and required more than 500 rail cars), to the 1998 arrest of the Unabomber, whose nationwide attacks included homemade explosives sent through the mail. The agency has even helped deliver the Hope Diamond to the Smithsonian in 1958.

Today's U.S. Postal Inspection Service has more than 2,700 employees, headquartered in Washington, D.C., and working in offices stretching from Los Angeles to New York. Each year, they arrest roughly 2,500 suspects for drug trafficking and money laundering through the mail. 

For a unique look inside the work of the USPIS-its history, achievements, and artifacts-members of the public can now explore an exhibit called "Behind the Badge" at the National Postal Museum in Washington, D.C.

The "Behind the Badge" exhibit is open from 10am-5:30pm, seven days a week except for Christmas Day, through December 2015. Admission is Free.

Read more about the USPIS here.