Mexico and the United States exercise sovereignty that is increasingly transnational and less absolute with respect to migration. This is evident in changes to Mexico's norm of non-intervention and the United States' plenary power doctrine, two doctrines rooted in international sovereignty. Both have historically defined sovereign authority in absolute terms, avoiding any foreign influence or domestic limitation. The non-intervention norm prohibits Mexican foreign relations from interfering in another state's domestic affairs. Traditionally, it barred a foreign policy on migrants in the United States, which led to Mexico's "no policy" on migrants. The U.S. plenary power doctrine labels immigration law as immune from judicial review because the political branches have complete, "plenary" authority over it. Traditionally, the plenary power doctrine barred constitutional limitations to this migration authority.
Sovereignty Migrates in U.S. and Mexican Law: Transnational Influences in Plenary Power and Non-Intervention,
40 Vanderbilt Law Review
Available at: https://scholarship.law.vanderbilt.edu/vjtl/vol40/iss5/3