MCI Telecommunications Corp. v. AT&T Co.

MCI Telecommunications Corp. v. AT&T Co., 512 U.S. 218 (1994), was a United States Supreme Court case about whether the Federal Communications Commission could set aside the requirement that each telecommunications common carrier file a tariff establishing fixed terms and prices for its services.

Congress had directed in that common carriers must file tariffs, which the Court said was a central part of the Communications Act of 1934. During an era of deregulation in the 1980s, the FCC decided — based on its judgment that there was robust competition in the market for long-distance calling — to set aside this requirement through its authority under to "modify any requirement."

AT&T filed a complaint against MCI, one of its competitors, after MCI chose not to file a tariff. The case eventually reached the Supreme Court through a petition for certiorari filed by MCI.

The Supreme Court held that statutory authorization to "modify" does not extend to setting aside entirely such a significant statutory mandate.