On May 12, 2015, the U.S. District Court for the District of Columbia partially granted a request for a preliminary injunction against the enforcement on new Interior Department rules which are intended, under the Department's reading of the Lacey Act, 18 U.S.C. Section 42, to prohibit the interstate transportation of listed "injurious species"; the species in this matter are the Reticulated Python and the Green Anaconda. These species are raised and sold in commerce, but if they escape, they can become dangerous predators. The case is United States Association of Reptile Keepers, Inc., v. Jewell. Although the case make be about snakes, it serves as a reminder that a public agency is not permitted to exceed its authority when promulgating rules.

In 2010, the Department proposed a new rule listing nine constricting species as "injurious", and thereby proposed to prohibit their importation and interstate transportation. A final rule, affecting the Reticulated Python and the Green Anaconda, was promulgated in March 2015, and was immediately challenged by the plaintiff. The association alleges that the Department was without legal authority to issue these rules, and that their implementation would be financially ruinous. After reviewing the text of the Lacey Act and its legislative history, the District Court agreed with the plaintiffs that the Department had exceeded its authority in promulgating these rules, and granted a partial preliminary injunction. As written, the District Court concluded, the interstate transportation of these species--that is within the 50 States--is not prohibited. Insofar as the Department argued that its interpretation of the law was entitled to "Chevron" deference, as contemplated by Chevron, U.S.A. v. Natural Resources Defense Council,467 U.S. 837 (1984), the District Court held that such deference does not extend to criminal statutes such as the Lacey Act.

The District Court was, however, mindful of the destruction wreaked by the Burmese Python in Florida, which has "accomplished a staggering depletion of native wildlife species" in Florida. Therefore additional hearing are scheduled to define the exact parameters of any injunction. The District Court was also worried that these species would find Florida and Texas to be very hospitable if they ever escaped confinement.