49 CFR 383.23: Commercial driver's license.

(a) General rule. (1) No person shall operate a CMV unless such person has taken and passed knowledge and driving skills tests for a CLP or CDL that meet the Federal standards contained in subparts F, G, and H of this part for the CMV that person operates or expects to operate.

(2) Except as provided in paragraph (b) of this section, no person may legally operate a CMV unless such person possesses a CDL which meets the standards contained in subpart J of this part, issued by his/her State or jurisdiction of domicile.

(b) Exception. (1) If a CMV operator is not domiciled in a foreign jurisdiction that the Administrator has determined tests drivers and issues CDLs in accordance with, or under standards similar to, the standards contained in subparts F, G, and H of this part, 1 the person may obtain a Non-domiciled CLP or Non-domiciled CDL from a State that does comply with the testing and licensing standards contained in such subparts F, G, and H of this part, so long as that person meets the requirements of § 383.71(f).

(2) If an individual is domiciled in a State while that State is prohibited from issuing CDLs in accordance with § 384.405 of this subchapter, that individual is eligible to obtain a Non-domiciled CLP or Non-domiciled CDL from any State that elects to issue a Non-domiciled CDL and which complies with the testing and licensing standards contained in subparts F, G, and H of this part, so long as that person meets the requirements of § 383.71(f).

(3) If an individual possesses a CLP, as defined in § 383.5, the individual is authorized to operate a class of CMV as provided by the CLP in accordance with § 383.25.