In the case of Federal Trade Commission v. American Tobacco (264 U.S. 298 (1924)) it was held that Agencies cannot conduct 'fishing expeditions' for information by issuing subpoenas. If an agency's request for information exceeded that agency's jurisdictional limits, you have the right to go to court and have them quash the subpoena. The modern rule about 'fishing expeditions' was later explained in United States v. Morton Salt (338 U.S. 632 (1950)), where the US Supreme Court substituted the test, "is the Agency request for information reasonable?" There is a substantial burden on the person being subpoenaed to show that the request is not reasonable. In general, an Agency has broad powers to ask for any information related to any tasks relevant to that Agency's jurisdiction.