The Centers for Disease Control & Prevention’s (CDC) “Dog Rule” (42 CFR § 71.51); Promulgation under the Administrative Procedure Act; 5 USC § 706(2)(C); Whether the microchip & age importation requirements in the Rule fell under the CDC’s authority; 42 USC § 264; Whether the requirements were “arbitrary & capricious”

[This appeal was from the WD-MI.] The court affirmed the denial of plaintiffs’ request to enjoin defendant-CDC from implementing the modified “Dog Rule,” holding that they were unlikely to succeed on the merits of their claim that the CDC lacked authority to issue the age and microchip requirements in the Rule. To prevent rabid dogs from entering the U.S., the CDC first implemented the Dog Rule in 1956, which set requirements for importing dogs. In 2024, it updated the Rule, imposing new requirements—the dogs must be microchipped and at least 6 months old. Plaintiffs (the U.S. Sportsmen’s Alliance and two individuals) sued, arguing that these requirements exceeded the CDC’s authority and were “arbitrary and capricious.” They sought a preliminary injunction. The district court denied the motion. The court agreed. It concluded that the CDC properly relied on § 264(a), which provides the CDC with the right to make and enforce regulations for the prevention of communicable diseases from foreign countries, including “‘inspection . . . and ‘other measures, as in [its] judgment may be necessary.’” The court held the microchip requirement was “statutorily authorized under the inspection provision because it is a means through which the CDC can carry out the inspections at the port of entry.” And the age requirement created “another way to ascertain the quality or condition of the dogs. Puppies under six months of age are generally uncoordinated, but that is also true of dogs infected with rabies. . . . Thus, the minimum age requirement ensures that officials at the port of entry are better able to identify potentially rabid dogs.” The court added that this requirement also fell under the “‘other measures’ catchall provision[.]” It further held that plaintiffs were unlikely to be able to show that the Rule is “arbitrary and capricious. The CDC, after conducting notice and comment rulemaking, reasonably concluded that fraudulent documents allowed rabid dogs to get into the country. By imposing the microchip requirement, the agency has made it harder to commit that fraud. And the minimum age requirement made it easier to spot potentially rabid dogs before they enter the country and ensure that rabies vaccinations were effective. It is reasonable for the CDC to have drawn the conclusions it did on this record.”