Alright, I’m one of those three lawyers.
As set forth in the DEA regulation on this issue, 21 CFR Section 1301.26, anyone who seeks to import a controlled substance for personal medical use must satisfy all of the following requirements:
(a) The controlled substance is in the original container in which it was dispensed to the individual and
(b) The individual makes a declaration to an appropriate official of the US Customs Service stating:
1) The controlled substance is possessed for his/her personal use, or for an animal accompanying him/her
2) The trade or chemical name and the symbol designating the schedule of the controlled substance if it appears on the container label, or if such does not appear on the label, the name and address of the pharmacy of practitioner who dispensed the substance and the prescription number if any; and
(c) The importation of the controlled substance for personal medical use is authorized or permitted under other Federal laws and state law.
The “Controlled Substances Trafficking Prohibition Act” (“the act”) (Pub. L. 105-357), was introduced into the US House of Representatives on April 1, 1998, to amend the Personal Medical Use Exemption. It was signed into law by the president on November 10, 1998. The Act addressed the fact that large quantities of controlled substances were being brought into the US from Mexico by individuals misusing the exemption in order to divert pharmaceutical controlled substances into illicit channels. The bill amended the CSA to prohibit any US resident from entering the US with more than 50 dosage units of a controlled substance through a land border crossing with Mexico or Canada unless they posses a valid prescription for the substance issued by a properly licensed US physician. This does not mean that any US resident may enter the United States with 50 dosage units of a particular controlled substance “no questions asked.” Rather, the resident must satisfy all the requirements set forth in 21 CFR 1301.26. States may impose additional requirements as well.
For example, if there is evidence that the drugs are not for legitimate personal medical use (e.g. the same person has made repeated attempts over a short time period to import new packages of controlled substances for claimed personal medical use; or the person has a variety of different controlled substances under circumstances that are indicative of diversion), the importation does not comply either with §956(a)(1) nor the DEA regulations and therefore must be disallowed.
Furthermore, the requirement specified in 21 CFR 1301.26(c) – that the importation for personal medical use is authorized or permitted under other Federal laws and state law – must be satisfied regardless whether the person importing is a US resident with no more than 50 dosage units of a controlled substance. For example, if a person were seeking to import a particular controlled substance for personal medical use, and the Food and Drug Administration advised the United States Customs Service that importation of the drug should be disallowed under the Food, Drug, and Cosmetic Act, the importation would not comply with 21 CFR 1301.26(c) and would have to be denied.
In the same way, if a person sought to import a controlled substance for purported personal medical use when entering the United States in a border state that prohibits either the importation or possession of the controlled substance, such importation must be disallowed under 21 CFR 1301.26(c).