§ 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.