By Hallie Lipsey*
In the midst of disputes regarding costs, immigration, and international standing, President Trump may be neglecting one of the greater obstacles to the completion of the wall he has proposed to build along the Mexican border: the jaguar.
The jaguar, along with 110 other animal and plant species, is protected under the Endangered Species Act. These animal species, ranging from the California Condor to the Gray Wolf, are listed as either threatened or endangered, and they possess habitats ranging from the American Southwest to Northern Mexico, precisely where the border wall would be constructed. Among the statutory protections afforded to these species, the Endangered Species Act prohibits the unlawful “taking” of a protected species by any entity, private or public.
A “taking” is defined under the ESA as any activity that results in the “harassing, harming, pursuing, hunting, shooting, wounding, killing, trapping, capturing, or collecting” any endangered species.  The primary question for the Trump administration, then, hinges on whether the completion of a wall would constitute a taking under the Endangered Species Act.
In applying the Endangered Species Act, the Supreme Court held that a “taking” could result from a government project which eradicated the population of a known endangered species or destroyed its critical habitat. In that case, environmental groups worked to enjoin the Tennessee Valley Authority from completing a dam because it would destroy the only remaining population of the snail darter, a small fish. Even though the project was almost complete, the court held the dam could not be completed under the Endangered Species Act. It stated, “The plain intent of Congress in enacting this statute was to halt and reverse the trend toward species extinction, whatever the cost.”
While little research has been completed on the effects of President Trump’s proposed wall, one study concerning the wall already completed along the Mexican border highlights the danger to the threatened animal populations this new project might pose. According to the findings, new barriers would increase the number of animal species at risk. Three geographic regions were noted in particular because of their “high richness of species at risk from…construction of potential new barriers.” For 16 species, up to 75% of their habitats could be restricted by the wall.
A previous study from 2007 detailed the decline of carnivores, including the protected Gray Wolf, along the United States-Mexico line.  It focused, however, on the devastating effect a wall might have on neotropical cats, noting that in the United States there were no known breeding populations of jaguars and only two populations of ocelots.
The wall, therefore, poses a unique threat to the continued viability of these endangered species and could thus be determined a “taking” under the Endangered Species Act. While the wall might not immediately result in the killing of these animals, it would limit the critical habitat and reduce mating opportunities. A European study expressly described the acute danger of fences on wildlife populations. It found that fences can “curtail animals’ mobility, fragment populations and cause direct mortality.”
However, President Trump might be able to use a small loophole already exploited by President Bush to override the protections of the Endangered Species Act. The REAL ID Act, a law enacted ostensibly to ensure the security and authenticity of identification documents such as driver’s licenses, contains a little-known clause, §102 (c), which granted the government extraordinary power. It permitted the Secretary of Homeland Security to waive any legal requirements that the Secretary determines necessary when building security infrastructure. When constructing the border wall for President Buff, former Secretary Michael Chertoff used §102 (c) to waive seven environmental laws, including the Endangered Species Act.
It did not take long for a case to arise challenging the constitutionality of the waiver provision. The Defenders of Wildlife sued, claiming that the provision violated the Presentment Clause of the Constitution because it amounted to a partial repeal of the law similar to a line item veto, previously ruled unconstitutional. The plaintiffs argued that the provision curtailed existing laws, but the D.C. District Court distinguished the provision in the REAL ID Act from the line item veto. It held that the Secretary was enabled to only to suspend legislations rather than to alter it or cancel it. Furthermore, the Secretary’s power extended only to the activities deemed necessary to complete the project, and it remained otherwise in affect. An appeal to the Supreme Court was denied.
A second lawsuit was brought in Texas when two government water districts and environmental groups sued under similar grounds. The plaintiffs here too lost on the issue concerning the Presentment Clause. Here, though, the plaintiffs also argued that the provision violated the states’ rights under the 10th Amendment. They stated that the waiver was so broad and vague as to place the state government officials in a position of not knowing which state and local laws remain in effect. They also stated such a power amounted to a ‘commandeering’ of its local government. The court held that these arguments were “more rhetorical than substantive.” However, the case stopped in the District Court, and these issues were never litigated at the Circuit level.
The Trump Presidency could renew the fight pitting the Secretary of Homeland Security against the Endangered Species Act. The fence could result in the taking of a protected animal, but it will be for the courts to determine whether or not the Secretary can legally neglect to avoid such takings.
The views and opinions expressed in this blog are those of the authors only and do not reflect the official policy or position of the Michigan Journal of Environmental and Administrative Law or the University of Michigan.
*Hallie Lipsey is a Junior Editor on MJEAL. She can be reached at firstname.lastname@example.org.
 IPaC Trust Resources Report, U.S. Fish and Wildlife Serv., Trump Wall (2016).
 Tennessee Valley Auth. v. Hill, 437 U.S. 153, 172 (1978).
 Id. at 171.
 Id. at 193.
 Id. at 184.
 Jesse R. Lasky, Conservation Biogeography of the US–Mexico Border: A Transcontinental Risk Assessment of Barriers to Animal Dispersal, 17 Diversity & Distributions 581 (2011).
 Id. at 1.
 Kevin Crooks et al., Neotropical Cats in Southeast Arizona and Surrounding Areas: Past and Present Status,14 Mastozoología Neotropical 189, 189-199 (2007).
 Id. at 192.
 Jennifer Dubrulle et al., Border Fences and Their Impacts on Large Carnivores, Large Herbivores and Biodiversity: An International Wildlife Law Perspective, Rev. of European, Comp. and Int’l Envtl. L. 25(3) (Oct. 7, 2016), https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2848898.
 REAL ID Act of 2005, Pub. L. No. 109—13, § 102(c), 119 Stat. 302 (2005).
 Dinah Bear, Border Wall: Broadest Waiver of Law in American History, (2009), http://www.ciel.org/Publications/BorderWall_8Feb09.pdf (citing Critics Blanch at Dodging Laws to Build Border Wall, Congressional Weekly, Feb. 21, 2005, at 442.).
 Defs. of Wildlife v. Chertoff, 527 F. Supp. 2d 119 (D.D.C. 2007).
 Id. at 123.
 Id. at 124.
 Cty. of El Paso v. Chertoff, No. EP-08-CA-196-FM, 2008 WL 4372693, 1 (W.D. Tex. Aug. 29, 2008).
 Id. at 6-7.
 Id. at 9.
 Id. at 10.