What is a migrant death? An operational definition for a more accurate enumeration of migrant mortality along the US-Mexico border.

Over the last forty years an indeterminate number of persons, ranging from thousands to tens of thousands, have died along the US-Mexico border during migration, fleeing poverty, armed conflict, situations of violence, and disasters. An accurate accounting of migrant deaths along the southern US border is the first step toward an understanding of the extent and the contributing factors of these deaths. In this article, we describe a key aspect of our collaborative work aimed at developing a more representative account of migrant mortality along the southwestern US border: the determination of criteria for inclusion of specific forensic cases as "migrant." Our intention is not to propose a definition of "what is a migrant death" applicable to all contexts and situations but rather one specific to the US-Mexico border region. Our main impetus is to build and launch a web portal to track and map migrant deaths at the US-Mexico border. The criteria we have identified are based on an examination of death data collected by various agencies in the four border states (California, Arizona, New Mexico, and Texas) and at the federal level by the National Missing and Unidentified Persons System (NamUs). They include a) context of human remains discovery; b) identification media/documentation; c) geographic setting; and d) personal effects. Taken together, these criteria will facilitate our determination, case by case, of the probability that human remains found along the United States side of the border may be from a person in the context of migration.

Map silences and chronic humanitarian crises: Spatial patterns of migrant mortality in South Texas, 2009-2020.

Forensic and humanitarian interventions deployed to address migrant death in US southwestern border states have become increasingly prevalent over the past four decades. In this paper we address two persistent issues specific to the Texas-Mexico border context. First, we present the first comprehensive geospatial analysis of migrant deaths in South Texas, establishing a twelve-year (2009-2020) mortality profile. And second, we introduce the concept of necrosilences and its implications to both forensic and humanitarian work and usage of geospatial tools. We applied ANOVA, spatial statistics, and cluster analysis to test the relationships of migrant mortality point locations throughout South Texas, an area comprised of ten counties with some of the highest reported migrant deaths in the state. Our findings demonstrated that unidentified human remains that corresponded to migrants were found most consistently in jurisdictions inland from the Mexican border. Further, the map visualizations highlighted vast areas seemingly devoid of migrant deaths. These "empty" areas are emblematic of necrosilences. That is, instances where there is a lack of access or accounting rather than no death incidences. We conclude by discussing the importance of visualizing necrosilences.

Migrant deaths at the Arizona-Mexico border: Spatial trends of a mass disaster.

Geographic Information Science (GIScience) technology has been used to document, investigate, and predict patterns that may be of utility in both forensic academic research and applied practice. In examining spatial and temporal trends of the mass disaster that is occurring along the U.S.-Mexico border, other researchers have highlighted predictive patterns for search and recovery efforts as well as water station placement. The purpose of this paper is to use previously collected spatial data of migrant deaths from Arizona to address issues of data uncertainty and data accuracy that affect our understanding of this phenomenon, including local and federal policies that impact the U.S.-Mexico border. The main objective of our study was to explore how the locations of migrant deaths have varied over time. Our results confirm patterns such as a lack of relationship between Border Patrol apprehensions and migrant deaths, as well as highlight new patterns such as the increased positional accuracy of migrant deaths recorded closer to the border. This paper highlights the importance of using positionally accurate data to detect spatio-temporal trends in forensic investigations of mass disasters: without qualitative and quantitative information concerning the accuracy of the data collected, the reliability of the results obtained remains questionable. We conclude by providing a set of guidelines for standardizing the collection and documentation of migrant remains at the U.S.-Mexico border.