Skip to main content
You are the owner of this article.
You have permission to edit this article.
Migrants taking longer, deadlier routes across border, UA study finds
alert top story

Migrants taking longer, deadlier routes across border, UA study finds

A blanket that may have belonged to a migrant border crosser lays in a wash north of Sasabe on the eastern foothills of the Baboquivari Mountains. Remains of over 200 migrants who attempted to cross the U.S. - Mexico border were found along the Arizona border in 2020.

Migrants are taking longer, more dangerous routes across Arizona’s border with Mexico, making the journey even deadlier than it was years ago, according to a new study from the University of Arizona.

Researchers at the UA’s Binational Migration Institute traced three decades of migrant deaths in Southern Arizona, based in large part on records maintained by the Pima County Office of the Medical Examiner. The study, done in collaboration with medical examiner staff, showed migrant deaths continued to rise, despite fewer migrants crossing the border, and the locations of those deaths shifted to ever more remote areas.

“Though fewer migrants are crossing, they continue to die in large numbers and are perishing in some of the most treacherous and rugged terrain within southern Arizona,” Daniel Martinez, co-director of the Binational Migration Institute, said in a news release Monday. “The lethality of crossing through southern Arizona has generally increased over the past 20 years.”

The study comes as the long-running crisis of migrant deaths in Southern Arizona appears to be worsening. Last year, the Pima County medical examiner received the remains of 209 migrants found in Pima, Santa Cruz, Cochise and Yuma counties, the highest annual total since 2010. Other sets of remains found in Maricopa County made 2020’s total of 227 the highest recorded. So far in 2021, the remains of 51 migrants have been found.

Since the crisis began in the early 2000s, the remains of more than 3,400 migrants have been found and reported to medical examiners. But those records only paint a partial picture of the crisis. An unknown number of migrants died, but their bodies were never found.

Migrant deaths are “not a partisan issue,” said Robin Reineke, an assistant research social scientist in the UA’s Southwest Center.

“We have seen multiple federal administrations come and go, and the crisis of unnecessary loss of life in the borderlands continues,” Reineke said. “It’s important to be informed about this issue before we undertake immigration and border control policies.”

Fewer crossings, more deaths

To show the increased risk to migrants, the UA researchers compared the number of remains found each year with Border Patrol apprehensions, which are often used as a proxy for overall illegal border crossings.

Border Patrol apprehensions in the agency’s Tucson Sector peaked in 2000 with more than 600,000 apprehensions. That year, the Pima County medical examiner received the remains of 70 migrants. By comparison, Tucson Sector agents made about 66,000 apprehensions last year and the medical examiner received the remains of 209 migrants.

To simplify the comparison, the medical examiner received an average of 32 sets of remains per 100,000 apprehensions in the early 2000s. In the period from 2014 to 2020, that rate rose to 244.

To explain this counter-intuitive outcome, the UA study traced four “funnel effects” that built on each other from the 1990s to 2020 and pushed migrants into “remote and dangerous areas.”

In the initial funnel effect in the 1990s, undocumented immigration had not yet concentrated in Southern Arizona and the medical examiner did not see large numbers of migrants’ remains.

During those years, the Border Patrol implemented a “prevention through deterrence” strategy, but the effects were relatively small in Southern Arizona at first. Under that strategy, federal officials expected “undeterred migrants would be forced to cross through more remote and dangerous desert areas in which the U.S. Border Patrol believed they would have a tactical advantage to apprehend undocumented border crossers,” according to the study.

The Border Patrol’s strategy pushed migrants out of major cities, such as San Diego and El Paso, and migration began to increase in Southern Arizona. During that period, many of the remains handled by the medical examiner were recovered in the Interstate 10 corridor between Tucson and Phoenix and along the Interstate 8 corridor near Yuma.

The number of remains tripled during the second funnel effect, which ran from 2000 to 2005. The crackdown pushed migrants away from smaller cities, in part by building border fences in the urban areas of Nogales and Douglas. Many of the remains were found on the Tohono O’odham Nation reservation and the Buenos Aires National Wildlife Refuge.

In the third funnel effect from 2006 to 2013, the Border Patrol adopted a “defense in depth” strategy that involved surveillance towers and checkpoints, which resulted in migrants traveling greater distances in remote areas. Operation Streamline, a fast-track prosecution program, began in Tucson’s federal court to increase the consequences for migrants caught crossing the border illegally. Apprehensions decreased and migrant remains often were found in more remote areas on or near the Tohono O’odham reservation.

In the “localized funnel effect” from 2014 to 2020, apprehensions in the Tucson Sector decreased to levels not seen since the early 1990s. More Central Americans crossed the border, particularly Guatemalans, and more people tried to apply for asylum, rather than cross the border clandestinely. Remains often were found in the desert west of Tucson on Organ Pipe Cactus National Monument and the Cabeza Prieta National Wildlife Refuge.

In response to an inquiry from the Arizona Daily Star, Tucson Sector officials said their “priority to preserve life has led to multiple initiatives to minimize the potential death of migrants,” such as “strategically placed rescue beacons in remote locations where individuals in distress can call for help” and responding to 911 calls from migrants in distress.

“As a proactive measure, USBP Tucson Sector also deploys BORSTAR, (specialized rescue teams) to areas where migrants are commonly found in distress,” said the statement from the Border Patrol.

Policy changes likely played a role

The researchers pointed to several forces shaping migrant deaths in Southern Arizona, such as border enforcement pushing migrants into remote and dangerous areas, the long history of the U.S. economy relying on labor from Mexico, and neoliberal economic reform in the 1990s that displaced hundreds of thousands of farmers throughout Mexico.

The researchers also cited three policy changes that likely played a role in migrant deaths in recent years.

First, Customs and Border Protection limited the number of people who could ask for asylum at legal ports of entry, known as “metering.” Second, the Migrant Protection Protocols forced asylum seekers to wait in Mexican border towns for months or years before they could attend immigration court hearings in the United States. Third, the Trump administration put in place a public health order known as Title 42 at the start of the pandemic, which allowed Border Patrol agents to quickly expel hundreds of thousands of migrants to Mexico.

“It is likely that these policies collectively contributed to migrant deaths in southern Arizona, as asylum-seekers became simultaneously discouraged from pursuing their lawful right to seek asylum in the United States and disillusioned about the likelihood of a successful outcome, opting instead to attempt to undertake a clandestine desert crossing,” according to the report.

Washington D.C. might be awash with politicians quick to cast blame on one side or the other, but experts say we are forgetting the real victims of the crisis who are the unaccompanied children at the U.S. and Mexican border. Interviews with legal experts and activists about the situation and the impact it is having on the children in detention centers waiting to be united with their families.

Contact Curt at 573-4224 or

Subscribe to stay connected to Tucson. A subscription helps you access more of the local stories that keep you connected to the community.

Get local news delivered to your inbox!

* I understand and agree that registration on or use of this site constitutes agreement to its user agreement and privacy policy.

Related to this story

Get up-to-the-minute news sent straight to your device.


News Alerts

Breaking News