Greg Grandin at The Nation:
Exhausted migrants crawl into caves and die, their remains never recovered or their bones, picked clean by carrion birds and other animals, disappearing into the sand. A Texas rancher recently told a reporter that only one out of every four bodies is found, which would put the death toll at well over 20,000. Patrick Ball, a statistician who works with human rights groups to count the victims of mass atrocities—93,000 in Syria, 69,000 in Peru, 18,000 in Timor-Leste—says that in order to arrive at an accurate ratio of total dead migrants to known remains, one would need “several independent enumerations of people you can identify as having died in the way you’re studying.” Each list would have to survey roughly the same area of the desert and include the name of the victim and the approximate location and date of death.
But migrants often don’t travel with identification, and the reliable data that do exist are spread out over California, Arizona, New Mexico and Texas, fragmented among morgues, hospitals, police departments and the Border Patrol. Some of those who perish during the trek don’t do so until they are well into the United States or have staggered back into Mexico.