Graciela Gomez Hernandez died a mile from a tower rated to track at seven miles

Before she died, Gomez Hernandez told her family in a WhatsApp message that she could see helicopters overhead and white Border Patrol trucks making periodic laps on the road below ^[5]. Between 2 and 3 p.m., her sister said, she sent her mother a last message. "I can't do it anymore," she whispered into her phone ^[3]. She had told the family about the plan only the day before. She hoped to work and send money to her three children and her parents in southern Mexico; her oldest son, 11, had asked for a bicycle ^[18]. A forensic crew collected her two weeks later, when much of her body had decomposed ^[4].

The camera systems added to these towers do two jobs, as the investigation describes them: they tell border-crossers from other people and animals, and they track movement ^[8]. A person who has stopped walking falls outside both. Dozens of the deaths in the California count were slow deaths of exposure that emergency aid might have averted ^[12].

At least 138 cases in four years works out to about 35 a year, one set of remains inside camera range roughly every 11 days ^[1]. MIT Technology Review's line-of-sight estimate was made across the wider set of hundreds of cases. Applied to the 138 alone, more than half means more than 69 people found where terrain did not block a camera's view of them ^[2]. The General Dynamics tower on the hilltop is rated for targets five to seven miles out, and Gomez Hernandez was at one mile, between a fifth and a seventh of the rated distance ^[3].

Range and sightline are two different tests. Marcia Dutra, a 36-year-old Brazilian woman, was found next to a border fence in July 2023, likely dead of heat exposure. The nearest tower with AI cameras sat 2,000 feet northeast above the edge of a plateau, out of sight of the slope where she lay, and according to a medical examiner's report the Border Patrol learned of her body from a group of migrants who had been apprehended ^[14]. Elvi Vasquez Bortolon, a 28-year-old Mexican man, had been dead more than five days from suspected hypothermia when he was found on a ridge near the wall in February 2024 ^[15].

Dying on Camera, the collaboration that produced both analyses, describes a year of reporting by MIT Technology Review and Times of San Diego ^[17]. On why anyone is in that terrain, the reporting is plain. The eastern edge of San Diego is a mile from the wall, and migrants walk 10 or 20 miles north through the mountains to evade the Border Patrol, coming out in smaller towns and on highways with fewer checkpoints ^[16]. The camera positions in the two analyses are matched to where bodies were found, not to where routes moved.

If you are standing up a detector of any kind, the grid worth drawing has two axes. Down the side, whether the sensor can produce the signal. Across the top, whether a named role owns the action, with a clock on it. Vendor decks and budget arguments live almost entirely in the first column, where range and classification accuracy are measured and the response is assumed. The test for each class a model can emit is which person gets paged and how many minutes they have. Where that name is missing, the deployment is producing a record for somebody to count later. The people found inside camera range on the California border were as old as 70 and as young as 5 ^[13].