President Donald Trump campaigned on border security and building a wall to, among other things, protect the United States from violence in Mexico and Central America.

But while his administration’s hardline approach to immigration has focused on dealing with an influx of migrants along the southern border, which Trump in speeches and tweets also ties to an influx of drugs and crime, he has not addressed a central part of the violence that drives the displacement of many families in Mexico and Central America: guns, the majority of which flow from the U.S. to Mexico.

Mexico’s murder rate is at an all-time high, according to that nation’s official figures. In 2018, the Mexican government recorded more than 30,000 intentional murders. A majority of those murders — 20,005 — were committed with firearms, according to government data.

Twenty percent of all homicides in Mexico last year were related to organized crime, according to a study from the University of San Diego, though the study noted the estimate was conservative and the figure was likely higher. The violence has been largely concentrated in drug trafficking regions in the northwest and the Pacific Coast region. The country, which has a population of 125 million, had more than 10,000 homicides recorded between January and May of this year.

A root cause of the violence that drives the displacement of many families in Mexico and Central America: the flow of guns from the U.S. to Mexico.

Research shows that a majority of guns in Mexico can be traced to the U.S. A report from the U.S Government Accountability Office showed that 70 percent of guns seized in Mexico by Mexican authorities and submitted for tracing have a U.S. origin. This percentage remains consistent, said Bradley Engelbert, a spokesperson for the Bureau of Alcohol, Tobacco, Firearms and Explosives. And the Trump has administration has recently taken steps to ease rules on gun exports, which enables manufacturers to sell guns in Mexico and Central America countries.

A report from the Center of American Progress found that the United States was the primary source of weapons used in crime in Mexico and Canada. Other countries in Central America can also trace a large proportion of guns seized in crimes to the United States. For example, the report found that from 2014 to 2016, 49 percent of crime guns seized in El Salvador were originally purchased in the U.S. In Honduras, 45 percent of guns recovered in crime scenes were traced to the United States as well.

Trump’s recent threat to impose tariffs on Mexican imports once again put his immigration policy front and center, with much of the focus on the issue of migrants attempting to enter the U.S.

During the standoff, which led to a deal between the two countries that avoided new tariffs, Arturo Sarukhan, a former Mexican ambassador to the U.S., suggested a different idea for stemming the flow of migrants.

“The U.S. should immediately stop the flow of guns and bulk cash across its southern border,” Sarukhan wrote in a tweet.

Still, the gun trafficking issue has largely been overshadowed by other immigration policy debates.

Gun laws in Mexico

On paper it’s significantly harder to legally purchase a firearm in Mexico than it is in the United States. So if it’s so difficult to buy a gun in Mexico, where do all of the country’s guns come from? The answer has as much if not more to do with U.S. gun policy than with Mexico’s, though the issue is rarely brought up in America’s political debates over gun control and border security.

The right to own guns is in Mexico’s constitution, as it is in the U.S., but Mexican gun laws are highly restrictive. The Mexican army is the only entity allowed to sell guns in the country, either to private security firms, private citizens or to local police. In fact, there is only one legal gun store in the country, which is also run by the Mexican army and located in Mexico City. Assault weapons and any weapon more powerful than a .38 caliber gun is banned from personal use, with few exceptions. Only the military is allowed to use high-powered firearms.

To apply for a gun license, applicants must have a crime-free record, employment, and to have served in the military, according to Mexico’s federal law of arms and explosives. But the army sells the majority of weapons to law enforcement entities, according to public records obtained by Stop U.S. Arms to Mexico, an organization whose goal is to stop illegal gun trade in Mexico. From 2010 to 2016, the army sold 166,763 firearms to local police forces — 55 percent of all the guns sold by the army during that period. Twenty percent – 67,725 – were retail sales to individuals.

The low number of approved licenses for carrying firearms is striking. Between 2013 and 2018 only 218 licenses to carry guns were issued, according to a public document issued by the Secretariat of National Defense (SEDENA), Mexico’s equivalent of the U.S. Department of Defense and the government agency in charge of issuing gun licenses.

But applications to acquire firearms have been on the rise. According to SEDENA, the agency received 55,567 applications to purchase firearms between 2013 and 2018. Between 2007 and 2012, during Felipe Calderón Hinojosa’s administration, 42,431 applications were reported. From 2010 through 2016, SEDENA reported the government selling 8,000 to 12,000 guns to the public annually.

Gun manufacturers in other countries, such as Germany, also supply weapons to Mexico. But lax U.S. gun laws and proximity to Mexico are key factors that drive guns south from the United States. An ongoing study of arms trafficking to Mexico and other Latin American countries, conducted by the Violence Policy Center, shows that military-style semi-automatic firearms comprise the majority of weapons smuggled south. These can be easily purchased in the United States, and are often harder to buy legally in other countries such as Canada, the United Kingdom and Switzerland, where automatic weapons are banned for civilians.

The right to own guns is in Mexico’s constitution, as it is in the U.S., but Mexican gun laws are highly restrictive.

“As long as you have that violence continuing in Mexico, you’re going to continue to have a demand for weapons,” said Duncan Wood, the director of the Mexico Institute at the Wilson Center, a Washington, D.C.-based think tank. “And the easiest way to get those weapons is from the United States.”

There have been efforts in Congress to create legislation to tackle firearm trafficking. In 2017, Reps. Norma Torres, D-Calif, Eliot Engel, D-N.Y., and Yvette Clarke, D-N.Y., introduced legislation to stop the flow of arms to Mexico. But these efforts have stalled in Congress.

“Trafficking illegal guns to and from Mexico is currently not a federal crime. It really doesn’t get much crazier than that,” Engel said in 2017. “This is just another example of how incredibly lax our gun laws are. Gun runners can cross state and international borders right now without fear of federal prosecution. The federal government is also prohibited from compiling data on this type of activity, also due to our arcane gun laws.”

How guns go south

So-called “straw purchasers” play a key role in firearms trafficking from the U.S. to Mexico and other points south. Typically “straw purchasers” are intermediary or middleman buyers who purchase and execute all the paperwork required for a legal firearm transaction on behalf of someone else. These purchasers are usually American citizens who adhere to U.S. gun laws, including passing a background check or meeting other applicable federal and state gun laws.

In many cases, “traffickers will run a ring of straw buyers,” said Kristen Rand, the legislative director for the Violence Policy Center. “The traffickers are exploiting the background check system because they just find people who can have the background check, and as long as they don’t raise suspicion with the dealer, then it’s difficult to identify that this is illegal.”

Straw buyers also evade suspicion typically by avoiding buying guns in bulk. Instead of going to stores and buying 20 or 40 guns at a time, straw buyers often buy only one or two weapons, Rand said.

Once the guns are purchased, traffickers face the next challenge: smuggling them across the border without getting caught. But traffickers have ways to surmount this obstacle as well.

For starters, guns can be disassembled into many parts, making them easier to hide.The Bureau of Alcohol, Tobacco, Firearms and Explosives, and Mexican government officials, have told the U.S. Government Accountability Office that smuggling weapon parts often limits bilateral collaboration to trace firearms, according to a 2016 GAO report that looks at U.S. efforts to combat gun trafficking.

A 2016 study by the Small Arms Survey, an independent research project that’s part of the Graduate Institute of International and Development Studies in Geneva, Switzerland, found that the majority of weapons trafficked from the U.S. into Mexico are smuggled over land in vehicles. The type of vehicles vary, as well as the manner in which weapons are concealed, factors that further complicate government efforts to stop the smuggling, the study noted.

Trafficking cases documented from 2009 and 2015 reveal the variety of ways gun runners hide guns in vehicles.

“Trafficked weapons were hidden in every conceivable location, including in the fuel tank, above the exhaust system, and under the bumpers,” the study said.

What the U.S. is doing to fight this now

ATF has four offices in Mexico, staffed by 11 special agents and 14 local staff that provide investigative support, according to Engelbert, the ATF spokesperson. The agency works with federal, state and municipal law enforcement authorities in Mexico, including the office of Mexico’s attorney general and the federal police, as well as the Mexican army, navy and customs agencies. ATF in Mexico assists local law enforcement with gun tracing and provides investigative support as well.

The agency’s personnel in Mexico initiate gun tracing operations when Mexican law enforcement request information on guns seized in homicides and other crime scenes in the country. The percentage of traces depends directly on the amount of weapons seized and reported by Mexican authorities.

And the amount of illegally trafficked weapons in Mexico is likely higher than official data suggests, since some weapons go unreported, and other weapons are stolen from the scene of the crime, said Bernard Zapor, a retired ATF agent who worked at the agency for 25 years. In some cases, Mexican authorities come across a firearm or a cache of firearms and don’t record the find or officially turn them over in a way that shows up in government statistics. “They might not ever report them. They might keep them,” Zapor said.

‘Trafficked weapons were hidden in every conceivable location, including in the fuel tank, above the exhaust system, and under the bumpers.’

Data sharing, or the lack thereof, is another lingering challenge facing ATF efforts to stop gun smuggling in Mexico. In 2012, President Enrique Peña Nieto, who left office last year, initiated a policy known as Ventanilla Unica, which limited access to ATF’s gun tracing database to certain officials in the Mexican attorney general’s office. In its 2016 report on gun trafficking, the Government Accountability Office noted that U.S. officials and some Mexican officials expressed concern that limiting access to the tracing database would complicate efforts for bilateral cooperation on gun trafficking.

This limited access to ATF’s tracing database under Peña Nieto continues to be a problem.

“ATF recommends more access to eTrace by allowing accounts for other federal, state and municipal law enforcement stakeholders,” an ATF spokesperson said in an email. “Mexico believes more accounts will lead to more immediate submissions of traces and therefore quicker results for generating leads in firearms trafficking investigations.”

Could stricter regulations mean less trafficking? Not necessarily

The availability of military assault weapons in the United States drives demand for American firearms in Mexico. “You can into gun stores in America and buy anything you need to outfit an army,” Rand said. “There’s so much lethal firepower so readily available. That’s the crux of the problem.”

Military assault weapons and ammunition bought in the U.S. can be sold for triple their original price in Mexico, which makes trafficking such a lucrative enterprise, said Zapor, the retired ATF agent.

“The firearm that I’m paying $390 for in Arizona, I’m selling in the Republic of Mexico for $4,000,” he said.

What’s more, informal firearm transactions on the so-called “gray market” — sales that occur on the margins of the legal, regulated gun market — are exceedingly difficult to monitor. That’s because straw buyers often resell the guns they buy online, where it is sometimes possible to purchase guns without a background check. And while some states require a licensed intermediary for private gun sales, others have no regulations on private sales.

The issue could be tackled by eliminating the gray market and requiring all sellers and purchasers to complete their transactions, including online sales, through a licensed dealer, Zapor said.

“The [gun] manufacturers don’t want this because the gray market accounts for millions, multiple millions of dollars in revenue from firearm sales,” Zapor said.

According to a 2017 study published in the Annals of Internal Medicine, 22 percent of people who acquired a gun in the U.S. in the previous two years did so without a background check.

Others pointed to lax regulations at gun shows as another factor driving gun trafficking.

“The exceptions made at gun shows certainly are a weak spot, I would say for the United States and for Mexico,” Wood said. “A lot of those purchases that take place in gun shows, typically take place close to the border. “

The lack of a federal database of gun serial numbers and transactions in the U.S. plays a role as well in stymying efforts to stop trafficking. U.S. gun laws prohibit a national registry, which means that there is no database tracking gun transactions. ATF is not allowed to keep a database of gun owners. (Mexico has a database of gun applications and licenses maintained by the Secretariat of National Defense.)

When ATF wants information on a firearm, the agency “will reach out to the gun store, and then they will rely on the gun story to provide that data,” said Colby Goodman, a firearm expert and former director of Security Assistance, an organization dedicated to making information about U.S. security and defense assistance programs publicly available. “But if the gun store is in on it, you’re not going to get the right information,” he added.

In interviews, several owners of gun stores along the U.S.-Mexico border said they did not think stricter regulations would stop gun trafficking.

Store owners and employees have their own methods for weeding out potential straw buyers, said John Dury, the owner of Dury’s Gun Shop in San Antonio, Texas. Typically potential buyers are asked what they’re planning to use the gun for, and if the buyer seems unsure or lacks knowledge about the gun, the employee can stop the purchase, Dury said.

“I don’t think the problem comes from legitimate stores,” Dury said. “I think that happens more in the stolen gun market than anything. If people know there are so many background checks, they don’t want to put their name in that.”

Mike Davis, the manager of AZ Guns in Arizona, said that an individual can buy a gun in a store in the state of Arizona and “go sell it in the parking lot” without a license.

The National Rifle Association did not respond to several requests for comment on whether existing gun laws play a role in gun trafficking and straw purchasing. However, in a 2009 statement on the topic, the NRA singled out Mexico’s restrictive gun laws as one of the factors that spurs weapons trafficking.

“Obviously, Mexico has a huge problem with rampant corruption that clearly cannot be blamed on the U.S.,” the NRA said in the statement at the time. “At the same time, Mexico has extremely prohibitive gun laws, yet has far worse crime than the U.S.”

How the U.S. government tackles gun trafficking — and what’s changed under Trump

There is an official government process in place to tackle the gun trafficking. But while critics have continued calling on the government to do more, it’s unclear whether the Trump administration has prioritized the issue.

Under an existing agreement, ATF and Homeland Security Investigations (HSI), a unit of the Department of Homeland Security that investigates illicit activities, work together to tackle gun trafficking to Mexico and Central America. The agencies’ cooperation is outlined in a memorandum of understanding, first reached in 2009, which established how the agencies should collaborate and share intelligence.

Currently, the two agencies meet monthly “to navigate the complexities associated with illegal international firearms trafficking and to cultivate relationships to improve the working knowledge of agencies,” said Matthew Bourke, a spokesperson for U.S. Immigration and Customs Enforcement.

The investigations agency also conducts probes and carries out arrests. According to government data, in 2018, HSI opened 1,269 investigations and made 546 arrests that were related to Counter Proliferation Investigations, a program that focuses on weapons trafficking.

According to government data, in 2018 Homeland Security Investigations opened 1,269 investigations and made 546 arrests that were related to a program that focuses on weapons trafficking.

Still, in recent years some government agencies have called for more action.

In its 2016 report, GAO issued another recommendation for the White House’s Office of National Drug Control Policy (ONDCP) calling for a revision to the Southwest Border Counternarcotics Strategy, a biennial report issued by ONDCP since 2007 outlining a strategy to curb the flow of illicit drugs, associated proceeds, and instruments of violence across the U.S.-Mexico border. The auditing agency recommended including in this document a set of indicators that would better measure efforts to curtail arms trafficking across the border. ONDCP has not revised the strategy since 2016 and has not yet implemented GAO’s recommendation.

“As of February of 2019, the time of our most recent outreach, there was no change in the situation,” said Jenny Grover, GAO analyst.

In March, Sen. Dick Durbin, D-Ill., requested an update to the 2016 GAO report that determined that 70 percent of firearms seized in Mexico come from the United States.

“The Trump administration talks tough, but they have turned a blind eye to this ‘iron river’ of guns flowing south. I’ve asked GAO to update its analysis of this firearms trafficking to help inform Congress’s efforts to address this challenge,” Durbin told the PBS NewsHour in a statement.

The need for more and better data on guns flowing south to Latin America from the U.S. cannot be overstated, said Matt Schroeder, a senior analyst at Small Arms Survey. Until the government has a better understanding of the problem, gun trafficking will remain a serious issue.

“Publicly available data on the arms trade — both legal and illegal — is scant,” Schroeder said. “The data that is available is often woefully inadequate for tracking illicit arms flows and identifying the sources of black market weapons.”

Editor’s note: This story was updated to differentiate between intentional and negligent homicides in Mexico’s homicide data, and to clarify the number of approved licenses for carrying firearms.