How we made the first comprehensive map of deaths along the US border’s “virtual wall”
Our 15-month investigation into death and surveillance along the US-Mexico border began with a simple question: Why did so many people die near government surveillance towers meant to help track and apprehend them? This story is part of Dying on Camera, a collaboration between MIT Technology Review and Times of San Diego. Journalists in both newsrooms spent the past….
The article describes a 15-month investigation by MIT Technology Review and Times of San Diego into migrant deaths near US-Mexico border surveillance towers. The project aimed to understand why so many people died in areas monitored by these towers, which are designed to track and apprehend migrants. The investigation involved reviewing government documents, visiting the border, and interviewing over 45 people, including Border Patrol agents, medical examiners, and tech company employees. The result was the first comprehensive map and analysis of deaths near these towers, covering cases from 2015 to 2026.
The investigation compiled data on migrant deaths from multiple sources, including organizations like No More Deaths, Humane Borders, and the Electronic Frontier Foundation (EFF). The team analyzed cases where three key details were confirmed: whether the person was crossing the border, where remains were found, and when they died. In Texas, where records were scarce, the team filed public records requests with sheriffs in 17 counties, receiving over 4,000 pages of reports. In Arizona, data from the Pima County Office of the Medical Examiner (PCOME) was used, covering 1,700 cases. No More Deaths provided nearly 1,000 cases from California, New Mexico, and parts of Texas. In total, the team analyzed nearly 4,000 cases, excluding those with insufficient location details.
Obtaining migrant death records in Texas was particularly difficult due to inconsistent record-keeping. Texas lacks a centralized system for tracking migrant deaths, unlike Arizona or New Mexico. The team requested records from sheriffs in 17 counties, but some counties took over a year to respond, while others charged fees ranging from $300 to $1,300. Many records were incomplete or lost during transitions between sheriffs. Additionally, most records did not specify whether the deceased was a migrant, requiring manual review. The team used AI tools like Anthropic’s Claude to extract coordinates for some counties but manually verified the results. Only 14 of the 17 counties provided usable records.
In Arizona, the Pima County Office of the Medical Examiner (PCOME) tracks migrant deaths and publishes a public data portal updated monthly. The team used this data, which includes GPS coordinates precise to within 300 feet and estimates of when individuals died. For New Mexico, No More Deaths obtained records from the state’s Office of the Medical Investigator, covering the entire state. The data included cases with GPS coordinates accurate to within a quarter-mile and information on decomposition levels to estimate time of death. The team included only cases where the location was known precisely enough for analysis.
The investigation focused on three main types of surveillance towers used by US Customs and Border Protection (CBP): Integrated Fixed Towers (IFTs), Autonomous Surveillance Towers (ASTs), and other tower types. IFTs are stationary towers with cameras and sensors, while ASTs are mobile towers equipped with AI-powered surveillance. The team used data from the Electronic Frontier Foundation (EFF), which has tracked over 600 towers, though government records suggest there are about 800 deployed. The locations of these towers were verified using satellite imagery. The analysis included towers installed between 2015 and 2026.
To create the map, the team matched migrant death locations with the proximity of surveillance towers. The analysis assumed that remains were found where the person died, though this may not always be accurate due to movement by animals, water, or people. The team excluded cases where the towers were unlikely to be relevant, such as deaths inside Border Patrol stations or in car crashes. The map includes nearly 4,000 cases, providing a visual representation of deaths near towers. The data reflects a variety of causes, from dehydration to drowning, all of which could have potentially been addressed by tower surveillance.
The investigation faced several limitations. Some counties in Texas did not provide records, and others charged high fees or provided incomplete data. The team relied on agencies to identify migrant deaths, but some records were clearly incorrect. Additionally, the analysis undercounts deaths in Texas because it excludes cases handled by local or state police. The team also excluded towers not catalogued by EFF, meaning some deaths near unrecorded towers were not included. Despite these challenges, the map represents the most comprehensive analysis of migrant deaths near surveillance towers to date.
