Sovereignty Migrates in US and Mexican Law: Transnational Influences in Plenary Power and Non-Intervention

Abstract

Mexico and the US exercise increasingly transnational, less absolute, sovereignty with respect to migration. This is evident in changes to Mexico's norm of non-intervention (NIV) and the US' plenary power doctrine (PPD), two doctrines sourced in international sovereignty. Both historically defined sovereign authority in absolute terms, avoiding any foreign influence or domestic limitation. NIV prohibits Mexican foreign relations from interfering in another state's domestic affairs. Traditionally it barred a foreign policy on migrants in the US, leading to Mexico's 'no policy' on migrants. PPD labels immigration law as immune from judicial review because the political branches have complete, 'plenary,' authority over it. Traditionally, PPD barred constitutional limitations to this migration authority.

Two events since 2001 inspire a transnational examination of changes in traditional sovereignty. First in Zadvydas v. Davis, the Supreme Court explicitly stated that the plenary power is 'subject to important constitutional limitations.' Second, Mexico actively lobbied US lawmakers for reforms to US immigration laws, an effort sometimes called the 'whole enchilada.' These developments point to the opposite of each doctrine's conclusion, that: there are constitutional limits to PPD and foreign relations may influence another state's lawmaking.

This examination is presented in five sections which: transnationally analyze international migration, describe PPD and NIV's foundations in absolute sovereignty, present Mexico's active foreign relations on migrants, discuss the US Supreme Court's use of the canon of avoidance to limit PPD, and conclude how these changes suggest a transnational influence in legal sovereignty conceptions.

Keywords: immigration, sovereignty, transnationalism, plenary power, non-intervention, Mexico, United States, international law, international relations, migration

JEL Classification: F22, J61, O15, R23