Quirky Constitutional Provisions Matter : The Tonnage Clause, Polar Tankers, and State Taxation of Commerce

In Polar Tankers, Inc. v. City of Valdez, the Supreme Court in 2009 struck down a City of Valdez levy that was in form a personal-property tax, but that primarily reached oil tankers using Valdez’s ports, on the ground that the levy violated the Tonnage Clause of the Constitution (“No State, shall, without the consent of Congress, lay any Duty of Tonnage”). The Tonnage Clause, part of the constitutional structure intended to ensure federal primacy in regulating commerce, was once a staple of litigation, but Polar Tankers was the first Supreme Court case decided under the Clause since 1935. Polar Tankers provides the opportunity to revisit a clause that might now seem quirky, but that was unquestionably important in the first century of the Republic, that raises many intriguing interpretive issues, and that can still (as this case shows) have significant effect