The legal status of the Plains Garter Snake within the United States is shaped by a layered system of federal, state, and local regulations that collectively govern the collection, possession, sale, and transport of native wildlife. At the federal level, the most significant pieces of legislation affecting the species are the Endangered Species Act, the Lacey Act, and the regulations administered by the United States Fish and Wildlife Service. The Plains Garter Snake is not listed as threatened or endangered under the Endangered Species Act, which means that the species does not receive the specific protections afforded to listed species, such as critical habitat designations or prohibitions on take. However, the absence of a federal listing does not mean the species exists in a regulatory vacuum, as multiple other federal and state laws apply.
The Lacey Act, originally enacted in 1900 and amended multiple times since, plays a significant role in regulating the interstate and international trade in wildlife, including reptiles. Under the Lacey Act, it is illegal to transport, sell, or acquire any wildlife that was taken in violation of state, tribal, or foreign law. This means that a Plains Garter Snake collected illegally under the laws of one state cannot be legally transported to or sold in another state, even if the receiving state has no restrictions on possession of the species. The Lacey Act effectively extends the reach of the most restrictive state-level regulations across jurisdictional boundaries, creating a framework in which compliance with local collection and possession laws is a prerequisite for legal interstate commerce.
The Convention on International Trade in Endangered Species of Wild Fauna and Flora, known as CITES, is an international agreement that regulates the cross-border trade in wildlife to prevent overexploitation. The Plains Garter Snake is not listed on any of the CITES appendices, which means that international trade in the species is not subject to CITES permitting requirements. However, keepers and breeders who export or import Plains Garter Snakes across national borders must still comply with the wildlife import and export regulations of the countries involved, which may include health certifications, quarantine requirements, and customs declarations.
Federal regulations also affect the Plains Garter Snake indirectly through environmental laws that govern land use and habitat protection. The National Environmental Policy Act, the Clean Water Act, and the protections afforded to wetlands under various federal programs all influence the management of habitats that support Plains Garter Snake populations. While these laws do not target the species specifically, they contribute to the preservation of the grassland and wetland landscapes on which the snake depends, and projects that affect these habitats may be required to assess their potential impacts on resident wildlife, including garter snakes.