49 U.S.C. § 31704

Vehicle registration

After September 30, 1996 , a State that is not participating in the International Registration Plan may not establish, maintain, or enforce a commercial motor vehicle registration law, regulation, or agreement that limits the operation in that State of a commercial motor vehicle that is not registered under the laws of the State, if the vehicle is registered under the laws of a State participating in the Plan.

( Pub. L. 103–272, § 1(e) , July 5, 1994 , 108 Stat. 1032 .)