Article I, Section 10, Clause 2:

No State shall, without the Consent of the Congress, lay any Imposts or Duties on Imports or Exports, except what may be absolutely necessary for executing it’s inspection Laws: and the net Produce of all Duties and Imposts, laid by any State on Imports or Exports, shall be for the Use of the Treasury of the United States; and all such Laws shall be subject to the Revision and Controul of the Congress.

In conjunction with several other provisions, particularly the Commerce Clause,1 the Import-Export Clause was designed to limit the states’ ability to interfere with commerce. To achieve this objective, the Clause generally prohibits States from imposing “imposts” or “duties” on imports and exports, absent congressional consent, except for purposes of covering charges associated with their inspection laws. The Clause further discourages States from imposing such duties by barring the States from using the funds collected from any such duties, instead requiring all funds to be deposited with the U.S. Treasury, and authorizing Congress to revise any State laws that impose duties.

Footnotes

1

U.S. Const. art. I, § 8, cl. 3.