"This Sidebar provides an overview of the NEA [National Emergencies Act] ; the military construction authorities available in the event of a declared emergency that the Administration may rely upon to deploy border fencing; and other statutory authorities that may provide the DOD with the authority to engage in certain construction operations. The Sidebar also discusses the availability of judicial review of a decision to invoke such authorities, along with critical questions that would arise in litigation over the lawfulness of a DOD border fencing project. Because the NEA and related military construction authorities do not appear to have been employed to construct barriers along the U.S. border, the invocation of such authorities for that purpose would raise a variety of novel legal issues, including (1) the circumstances in which conditions along the border rise to the level of a 'national emergency' that 'requires use of the armed forces,' and the circumstances in which military construction is 'necessary to support such use of the armed forces'; (2) the meaning of the term 'military construction' in the MCCA [Military Construction Codification Act] ; (3) how a court would review different segments of border wall construction; and (4) the relationship between military construction authorities and various other federal laws and constitutional considerations that shape the manner in which federal agencies carry out construction projects."
CRS Legal Sidebar, LSB10242
Congressional Research Service: https://crsreports.congress.gov/