49 U.S.C. § 31312

1. (a)If the Secretary of Transportation determines that a State is in substantial noncompliance with this chapter, the Secretary shall issue an order to—
   1. (1)prohibit that State from carrying out licensing procedures under this chapter; and
   2. (2)prohibit that State from issuing any commercial driver’s licenses until such time the Secretary determines such State is in substantial compliance with this chapter.
2. (b)A State (other than a State subject to an order under subsection (a)) may issue a non-resident commercial driver’s license to an individual domiciled in a State that is prohibited from such activities under subsection (a) if that individual meets all requirements of this chapter and the nonresident licensing requirements of the issuing State.
3. (c)Nothing in this section shall be construed as invalidating or otherwise affecting commercial driver’s licenses issued by a State before the date of issuance of an order under subsection (a) with respect to the State.