49 U.S. Code § 14505. State tax

A State or political subdivision thereof may not collect or levy a tax, fee, head charge, or other charge on—
(1)
a passenger traveling in interstate commerce by motor carrier;
(2)
the transportation of a passenger traveling in interstate commerce by motor carrier;
(3)
the sale of passenger transportation in interstate commerce by motor carrier; or
(4)
the gross receipts derived from such transportation.
Effective Date

Section effective Jan. 1, 1996, except as otherwise provided in Pub. L. 104–88, see section 2 of Pub. L. 104–88, set out as a note under section 1301 of this title.