The fire-related deaths of at least 39 migrants in a detention facility in Ciudad Juarez, just across the U.S. border with Mexico, will likely be found to have had several contributing factors.

There was the immediate cause of the blaze, the mattresses apparently set alight by desperate men in the center to protest their imminent deportation. And then there is the apparent role of guards, seen on video walking away from the blaze.

But as an expert on immigration policy, I believe there is another part of the tragedy that can’t be overlooked: the decadeslong immigration enforcement policies of the U.S. and Mexican governments that have seen the number of people kept in such facilities skyrocket.

In the aftermath of the fire, Felipe González Morales, the United Nations special rapporteur for human rights of migrants, commented on Twitter that the “extensive use of immigration detention leads to tragedies like this one.”

And the United States is a big part of that “extensive use” on both sides of the border.

Lengthy stays and fear of deportation

Today Mexico maintains a very large detention system. It comprises several dozen short- and long-term detention centers, housing more than 300,000 people in 2021.

By comparison, the U.S. immigration detention system is the world’s largest. It maintains 131 facilities comprised of government-owned Service Processing Centers, privately run Contract Detention Facilities, and a variety of other detention facilities, including prisons.

Mexico has laws in place that are supposed to guarantee that migrants in detention only endure brief stays and are afforded due process, such as access to lawyers and interpreters. The law also states that they should have adequate conditions, including access to education and health care.

But in reality, what migrants often face at these detention centers is poor sanitary conditions, overcrowding, lengthy stays and despair over the near certainty of deportation.

The fire in Ciudad Juárez was started after the migrants – men from Guatemala, Honduras, Venezuela, El Salvador, Colombia and Ecuador – learned that they were to be sent back to those nations, according to Mexican President Andrés Manuel López Obrador. Deportation would have ended their hopes of asylum in the U.S.

US immigration enforcement shifts south

Why Mexico was doing the deporting, not the U.S., has a great deal to do with how the two nations have collaborated to control illegal migration headed to the U.S., especially since the turn of the century. In the wake of the 9/11 terrorist attacks of 2001, U.S. authorities increasingly viewed immigration as a security issue – a pivot that affected not only U.S. domestic legislation on immigration but its bilateral relations with Mexico.

In 2006, Mexican President Felipe Calderón joined efforts with President George W. Bush on the Merida Initiative to wage a war on drugs in Mexico, build a “21st Century U.S.-Mexican border” and shift immigration enforcement into Mexican territory.

These efforts, supported by massive U.S. funding, continue today.

With this money, Mexico established naval bases on its rivers, security cordons and drone surveillance. It also set up mobile highway checkpoints and biometric screening at migrant detention centers, all with the goal of detecting, detaining and deporting largely Central American migrants attempting to reach the United States.

The intent was to shift U.S. immigration enforcement south of the border. In that respect, the policy has been successful. Figures from the Guatemalan Institute of Migration show that of the 171,882 U.S.-bound migrants deported to the Northern Triangle region of Central America – El Salvador, Honduras and Guatemala – in 2022, Mexico sent back 92,718, compared to the U.S.‘s 78,433.

Prevention through deterrence is not working

Mexico’s detentions and deportations have done little to stop the flow of migrants entering the country en route to the U.S.

Researchers at the University of Texas at Austin estimate that from 2018 to 2021, an annual average of 377,000 migrants entered Mexico from the Northern Triangle region. The vast majority were headed to the U.S. to escape violence, drought, natural disasters, corruption and extreme poverty.

Migrants are passing through Mexico in the thousands from multiple other countries as well, fleeing conditions in countries such as Haiti and Venezuela, as well as African nations.

Meanwhile, recent years have seen a toughening of border enforcement policies targeting asylum seekers at the U.S.-Mexico border. This started under the Trump administration but has been continued by President Joe Biden despite the Democrat’s campaign promises of a more “humane” immigration system.

Since 2019, Washington has adopted a series of policies that have either forced migrants presenting themselves at the U.S. southern border to apply for asylum while remaining in Mexico or expelled them back to their countries of origin.

This has created a bottleneck of hundreds of thousands of migrants at Mexico’s border towns and swelled the numbers entering detention facilities in Mexico.

By 2021, the number of immigration detainees in such centers had reached 307,679, nearly double what it had been in 2019.

As a result, many centers, including the one implicated in the fire, have suffered from overcrowding and deterioration conditions. A 2021 report by the immigration research center Global Detention Project extensively documented how the conditions and practices of Mexico’s immigration centers had led to widespread protest by detained migrants. Rioting and protests have become more common, with incidents taking place at facilities in Tijuana and the southern city of Tapachula in recent months.

No end in sight

The tragedy in Ciudad Juárez is unlikely to affect the steady flow of migrants entering Mexico in the hope of making it north of the border. For many, the options to take a different path to safety in the U.S. are simply not there.

Only a few can apply for refugee status in the U.S. from abroad, and the waits are long. Biden’s “humanitarian parole” program – which allows entry to the U.S. for up to 30,000 people a month – is only an option for those living in a handful of nations. It is also being challenged in court. And for the lucky few who manage to file for U.S. asylum, denial rates remain high – 63% in 2021 – while immigration court backlogs mean that fewer cases are being decided. Only 8,349 asylum seekers were actually granted asylum by U.S. immigration judges in 2021.

Meanwhile, the Biden administration’s incoming “transit ban” will mean anyone seeking asylum at the U.S. southern border from May 11, 2023 without having first applied for asylum en route, will be rapidly deported, many to Mexico.

The likelihood is the policy will only worsen the migrant processing bottleneck in Mexico, and add pressure on the country’s already volatile detention facility system.