Can the DEA enforce its requirement that doctors must be registered to issue prescriptions?

21 U.S.C. § 822(a)(2) provides, in pertinent part, that “[e]very person who dispenses, or who proposes to dispense, any controlled substance, shall obtain from the Attorney General a registration issued in accordance with the rules and regulations promulgated by him.” 21 U.S.C. § 822(e )(1) in turn provides that “[a] separate registration shall be required at each principal place of business or professional practice where the applicant . . . distributes or dispenses controlled substances . . .” 21 C.F.R. § 1301.12 repeats the requirement of having separate registrations for each “principal place of business or professional practice” and sets forth several exemptions from the registration requirements. 21 CFR § 1306.03(a ) purports to require that only physicians licensed in their states and registered with the DEA can prescribe controlled substances. Persons so registered are authorized to distribute or dispense those substances “to the extent authorized by their registration in conformity with the other provisions of this subchapter.” 21 U.S.C. § 822(b).A violation of the registration provisions of 21 U.S.C. § 822 is not a subject of 21 U.S.C. § 842(a) and therefore does not subject the violator to the sanctions set forth in 21 U.S.C. § 842(c ). Pursuant to 21 U.S.C. § 842(a), “[i]t shall be unlawful for any person” to do any of the things set forth in subsections 1 through 16 thereto. Failure to register under 21 U.S.C. § 822 is not one of the sixteen activities described as “unlawful” in § 842(a). Subsection 842(a)(2) prohibits a person “who is a registrant” from distributing or dispensing “a controlled substance not authorized by his registration to another registrant or other authorized person.” However, the plain language of that subsection indicates that its object is the distribution of (a) controlled substances not authorized by a person’s registration to (b) other registrants rather than the distribution of controlled substances that a registrant is authorized to distribute, albeit in another jurisdiction, to persons who are not registrants. It therefore cannot be used to regulate doctors.21 U.S.C. § 829(a ) and (b) provide that, with certain exceptions, “except when dispensed directly by a practitioner, other than a pharmacist, to an ultimate user,” no controlled substances defined in certain Schedules “may be dispensed without the written prescription of a practitioner.” Although it does not by its terms require a “valid” prescription, pursuant to 21 U.S.C. § 829(e)(2)(A), a “valid prescription” is defined as one that is issued for a legitimate medical purpose by a practitioner who has examined the patient. And 21 C.F.R. § 1306.04 provides that a prescription not issued in the course of professional treatment or research is not a prescription under § 829.   As the U.S. Supreme Court recited in U.S. v. Moore, 423 U.S. 122, 137, 96 S. Ct. 335, 343 fn. 13 (1975):On its face § 829 addresses only the form that a prescription must take. A written prescription is required for Schedule II substances. § 829(a ). . . The medical purpose requirement explicit in subsection (c ) could be implicit in subsections (a) and (b). Regulation § 306.04 makes it explicit. But § 829 by its terms does not limit the authority of a practitioner.See also Gonzalez v. Oregon, 546 U.S. 243, 274, 278, 126 S. Ct. 904, 925, 927-28 (2006). In other words, § 829 only requires that prescriptions take a certain form and has nothing to say about the DEA’s ability to regulate doctors who do not register.