The United States Postal Inspection Service (USPIS) is the law enforcement arm of the United States Postal Service. Its jurisdiction is defined as "crimes that may adversely affect or fraudulently use the U.S. Mail, the postal system or postal employees." The mission of the U.S. Postal Inspection Service is to support and protect the U.S. Postal Service, its employees, infrastructure, and customers by enforcing the laws that defend the nation’s mail system from illegal or dangerous use.