	Introduction

Over the last decade, migration to the United States from Central America—in particular from El Salvador, Guatemala, and Honduras (known collectively as the Northern Triangle)—has increased considerably. This is adding to a large backlog of asylum cases in U.S. immigration courts. In the past year, news reports of migrant "caravans" from the Northern Triangle traveling toward the U.S. border have sparked intense interest and many questions from Congress, including the following: What factors are contributing to the increase in migration from the Northern Triangle to the United States? Over time, weak institutions and corrupt government officials, economic growth that does not significantly reduce chronic poverty, rising levels of crime, and demand for illicit drugs result in insecurity and citizens' low levels of confidence in government institutions. Some contend that the United States' asylum policy, which allows asylum seekers to remain in the United States while they await a decision on their cases, has encouraged recent family and unaccompanied child migration to the country. Actions by Governments and International Organizations

		What is the United States doing to address the factors driving migration from the Northern Triangle?31

Under the U.S. Strategy for Engagement in Central America, the United States is working with Central American governments to promote economic prosperity, improve security, and strengthen governance in the region. In Mexico, UNHCR provides immediate and longer-term support by working with local and federal governments and alongside civil society and other partners. Aliens who wish to request asylum may do so at a U.S. port of entry before a CBP officer or upon apprehension by a CBP officer between U.S. ports of entry. To receive asylum, an alien must establish, among other requirements, that he or she is unable or unwilling to return to his or her home country because of past persecution or a well-founded fear of future persecution based on one of five protected grounds (race, religion, nationality, membership in a particular social group, or political opinion). A subsequent DOD news release announcing the deployment of active duty personnel in October 2018 stated that CBP " requested aid in air and ground transportation, and logistics support, to move CBP personnel where needed. Officials also asked for engineering capabilities and equipment to secure legal crossings, and medical support units. How does the Posse Comitatus Act limit the use of military personnel?85

The Posse Comitatus Act constrains how military personnel may be used in a law enforcement capacity at the border. Can the Department of Defense build the border wall?90

President Trump has contemplated proclaiming a national emergency pursuant to the National Emergencies Act (NEA) in order to fund a physical barrier at the southern border with Mexico using DOD funds. Chapter 15 of Title 10, U.S. Code—Military Support for Civilian Law Enforcement Agencies—provides general legislative authority for the Armed Forces to provide certain types of support to federal, state, and local law enforcement agencies, particularly in counterdrug, counterterrorism, and counter-transnational crime efforts. What authority does the President have to cut off aid to the Northern Triangle countries?111

Congress provided the President with significant discretion to reduce foreign assistance to Central America in FY2018. The act also requires the State Department to withhold 75% of assistance for the central governments of El Salvador, Guatemala, and Honduras until the Secretary of State certifies that those governments are addressing a variety of congressional concerns, including improving border security, combating corruption, and protecting human rights. The President's ability to modify assistance to the Northern Triangle countries for FY2019 will depend on provisions Congress may include in future appropriations legislation. What actions has the President taken to restrict eligibility for asylum?112

Citing constitutional and statutory authority, the President issued a presidential proclamation on November 9, 2018, to immediately suspend the entry into the United States of aliens who cross the Southwest border between ports of entry. The proclamation and the rule are being challenged in federal court.
Over the last decade, migration to the United States from Central America—in particular from El Salvador, Guatemala, and Honduras (known collectively as the Northern Triangle)—has increased considerably. Families migrating from this region, many seeking asylum, have made up an increasing share of the migrants seeking admission to the United States at the U.S.-Mexico border. In the past year, news reports of migrant "caravans" from the Northern Triangle traveling toward the United States have sparked intense interest and questions from Congress.
Many factors, both in their countries of origin and elsewhere, contribute to people's decisions to emigrate from the Northern Triangle. Weak institutions and corrupt government officials, chronic poverty, rising levels of crime, and demand for illicit drugs result in insecurity and citizens' low levels of confidence in government institutions. These "push" factors intersect with "pull" factors attracting migrants to the United States, including economic and educational opportunities and a desire to reunify with family members.
Addressing these factors is complex. Under the U.S. Strategy for Engagement in Central America, the United States is working with Central American governments to promote economic prosperity, improve security, and strengthen governance in the region. Since 2014, Mexico has helped the United States manage flows of Central American migrants, including a recent decision to allow certain U.S.-bound asylum seekers to remain in Mexico while awaiting U.S. immigration proceedings. The United Nations High Commissioner for Refugees (UNHCR)—in collaboration with local and federal governments and civil society—is providing immediate and longer-term support for Mexico's refugee agency and migrants in transit.
Central Americans who wish to request asylum in the United States may do so at a U.S. port of entry before a Customs and Border Protection (CBP) officer or upon apprehension by a CBP officer between U.S. ports of entry. Those requesting asylum at the border undergo screening to determine whether they can pursue an asylum claim. To receive asylum, a foreign national must establish, among other requirements, that he or she is unable or unwilling to return to his or her home country because of past persecution or a well-founded fear of future persecution based on one of five protected grounds (race, religion, nationality, membership in a particular social group, or political opinion). In 2018, President Trump, the Department of Homeland Security (DHS), and the Department of Justice (DOJ) took various actions to tighten the U.S. asylum system. These actions have been met with legal challenges. For example, on November 9, 2018, the President issued a presidential proclamation to suspend immediately the entry into the United States of aliens who cross the Southwest border between ports of entry. This proclamation and a related DHS-DOJ rule are being challenged in federal court.
Chapter 15, Title 10 of the U.S. Code provides general legislative authority for the Armed Forces to provide certain types of support to federal, state, and local law enforcement agencies. In October 2018, active-duty personnel were deployed to the Southwest border to provide assistance in air and ground transportation, logistics support, engineering capabilities and equipment, medical support, housing, and planning support. The Posse Comitatus Act constrains the manner in which military personnel may be used in a law enforcement capacity at the border. President Trump has contemplated proclaiming a national emergency pursuant to the National Emergencies Act (NEA) in order to fund a physical barrier at the southern border with Mexico using DOD funds.
Congress provided the President with significant discretion to reduce foreign assistance to Central America in FY2018, dependent on the governments of El Salvador, Guatemala, and Honduras addressing a variety of congressional concerns, including improving border security, combating corruption, and protecting human rights. The President's ability to modify assistance to the Northern Triangle for the remainder of FY2019 will depend on provisions Congress may include in future appropriations legislation.