River of Steel and Blood: When U.S. Gun Laws Become Mexico’s Nightmare

By Vanessa Tao '28

Guest Writer, Brown University

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Mexico has one of the highest rates of gun deaths in the world, with a staggering 160,000 people killed with a gun from 2015 to 2022. (1) The degree of violence during this period represents a 102% increase in gun-related homicides, with most of the bloodshed stemming from criminal organizations and cartels. (2) Yet, Mexico has only two gun stores in the country: a new one primarily targeted for hunters in Monterrey, Nuevo Leon, and the flagship Directorate of Arms and Munitions Sales, located on a heavily-guarded military base and run by the Mexican military. Mexico’s gun laws are fairly strict; although Article 10 of its Constitution allows citizens to possess arms in their home for security reasons, like the 2nd Amendment of the US Constitution, the Mexican government reserves the right to “determine the cases, conditions, requirements, and places” of gun ownership. (3) As a result of stringent regulations around owning and purchasing a gun, these two stores sell an average of only 38 guns to civilians a day. (4)

Where, then, are the rest of the hundreds of thousands of guns in Mexico coming from? The US Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) estimates that 380 guns are smuggled into Mexico from its northern neighbor, the US, every single day. (5) Around 68% of guns recovered at crime scenes in Mexico from 2016 to 2021 were traced back to American firearm manufacturers. (6) Despite these staggering figures, the ATF’s data is not comprehensive—the true number of US guns used to perpetrate crimes in Mexico may be much higher. (7) This so-called “iron river,” or the flow of guns from the 70,000+ licensed gun stores in the US, is magnifying the arsenals of Mexico’s organized crime groups, reaping catastrophic death rates and breaking down civilian safety. (8) The shortcomings of US gun control laws are spilling across the border, bringing its deadly impact to its neighbor in the south. 

Within US federal laws, individuals or businesses that sell firearms must obtain a Federal Firearms License (FFL) from the ATF. Moreover, gun vendors are required to conduct background checks through the National Instant Criminal Background Check System (NICS), report sales of multiple handguns to the ATF, and maintain records of sales. Licensed dealers must perform background checks on buyers to block purchases from convicted felons, fugitives, drug users, and those with certain mental health diagnoses. (9) The National Firearms Act (NFA) also imposes certain restrictions on modifications such as short-barreled rifles and silencers. (10) While these regulations create the foundation for a framework regulating gun sales, they currently leave serious gaps that are being exploited to enable substantial rates of firearm trafficking.

A significant loophole in US firearm regulations is the “gun show loophole,” or a gap in legislation that allows for private sellers to distribute guns without requiring them to maintain sales records or conduct background checks, unlike federally licensed dealers. Its name comes from an association with gun shows, but this loophole applies to all private sales of firearms. (11) Another way in which US legislation directly affects gun trafficking is the role of state-level laws in exacerbating the issue. In Texas, for instance, the state Constitution upholds broad “keep and bear arms” rights and does not require a permit, registration, or licensing of gun owners to purchase a weapon. (12) As a result of relaxed gun laws that allow for minimal accountability and oversight, a glaring blind spot is created that allows for trafficking. Texas’s geography as a border state, combined with its loose gun legislation, creates a perfect storm in which straw purchasers buy large quantities of high-powered weapons such as AR-15s and AR-47s and smuggle them across the border, where they end up in the hands of violent cartels and organized crime groups. The state is now a key supplier within the firearm black market, fueling violence and instability in Mexico. (13)

Beyond state-level legislation, however, is the landmark Protection of Lawful Commerce in Arms Act (PLCAA), enacted in 2005. It prohibits “qualified civil liability actions,” protecting the gun manufacturing industry from lawsuits related to unlawful firearm use by consumers. (14) PLCAA limits accountability from major distributors, essentially allowing them negligent practices that contribute to mass gun violence. In the most recent Supreme Court case related to this issue, Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, Mexico is accusing seven of the largest American gunmakers of maximizing profits through negligent practices that take advantage of permissive US gun legislation and knowingly aid the trafficking of firearms and supply military-style weapons to dangerous crime groups, thus harming Mexico’s citizenry. (15) This case poses two primary legal questions: whether US firearms directly cause injuries to Mexico, otherwise known as proximate cause, and whether manufacturers meet the bar of “aiding and abetting” illegal firearms trafficking through underhanded marketing practices and knowledge that their products are used unlawfully. (16) The implications of this case are crucial: if the Court agrees with Mexico’s position, it could open doors for additional litigation against US industries and their harmful effects across the globe, along with taking an important step towards holding large gun manufacturers accountable and hitting powerful gun lobbies on the domestic front. (17) 

However, the Supreme Court is currently expected to block the $10 billion lawsuit, after oral arguments on March 4, 2025, left the justices unconvinced that gun makers’ actions lead directly to the damage felt in Mexico. Justice Ketanji Brown Jackson argued that they “don’t really see exactly how the manufacturers are violating a particular federal or state law,” while Justice Elena Kagan questioned, “Who are they aiding and abetting in this complaint?” (18) If the ruling continues towards a dismissal, this case would only reinforce PLCAA’s strength, hindering future lawsuits against gun manufacturers and the harm they cause. It may allow US manufacturers even greater free rein to continue negligent, dangerous practices that contribute to increasing violence and death across the border, while at the same time setting a precedent to the rest of the world that US companies are protected from taking responsibility for the harms that they contribute to outside the country’s territory. 

This case emphasizes consistent tensions between the broad, mostly unfettered gun culture in the US and public safety measures, especially in light of the US’s high rate of gun deaths. For instance, in 2016, 10.5 per 100,000 people in the US were killed by a firearm—a rate significantly higher than other developed countries. (19) The US has more firearms per capita than any other country, a measure that stems from hundreds of years of tradition, history, and culture tied to gun ownership. As a result, Americans remain somewhat resistant toward gun control measures, with many favoring changes to mental health systems or school security measures instead of targeting guns directly. (20) However, any measures that would tighten firearm regulations in the US, such as universal background checks and other common-sense regulations, would also reduce the ease with which arms can be trafficked to facilitate violence outside of US borders. With the influence that the US wields, especially over its neighboring countries, it must remain conscious of the real-life ramifications of its own legislation and the precedent that it sets for the rest of the global climate. 

While the US grapples with its Second Amendment rights and how its cultural identity ties to firearms, Mexico is fighting for its fundamental right to live in peace and safety. As Professor Ieva Jusionyte, anthropologist at Brown University and author of Exit Wounds: How America’s Guns Fuel Violence Across the Border, observes in an interview with Duke University, “There is no justice, no accountability for violence, and no truth or closure for families who lost their loved ones. That, too, is how guns violate human rights.” (21) The stark reality of the impact of US guns on Mexico highlights the need for reforms that balance lawful gun ownership with regulations that have the potential to prevent thousands of deaths, restore a sense of safety to communities both inside and outside of the US, and strengthen security on both sides of the border. After all, the “iron river” carries a double meaning: it flows with both steel and blood. 

Endnotes

1. Everytown for Gun Safety Support Fund, “Damming the Iron River,” Everytown Research & Policy, May 21, 2024, https://everytownresearch.org/report/damming-the-iron-river/.

2. Ibid.

3. Kate Linthicum, “There Is Only One Gun Store in All of Mexico. So Why Is Gun Violence Soaring? - Los Angeles Times,” Los Angeles Times, May 24, 2018, https://www.latimes.com/world/la-fg-mexico-guns-20180524-story.html.

4. Ibid.

5. “Mexico Has 1 Gun Store but Is Awash in Firearms,” n.d., https://enewspaper.latimes.com/infinity/article_share.aspx?guid=6a94cd6a-dded-4e65-ba08-9cae86e65e74.

6. “Firearms Trace Data: Mexico - 2016-2021 | Bureau of Alcohol, Tobacco, Firearms and Explosives,” n.d., https://www.atf.gov/resource-center/firearms-trace-data-mexico-2016-2021.

7. Everytown for Gun Safety Support Fund, “Damming the Iron River,” Everytown Research & Policy, May 21, 2024, https://everytownresearch.org/report/damming-the-iron-river/.

8. Everytown for Gun Safety Support Fund, Daniel Semenza, and David Johnson, “GUN DEALERS IN THE UNITED STATES,” report, Inside the Gun Shop: Firearms Dealers and Their Impact, July 6, 2023, https://everytownresearch.org/wp-content/uploads/sites/4/2021/05/Inside-the-Gun-Shop-One-Pager.pdf.

9. Federal Firearms Laws, 18 U.S. Code § 922

10. Federal Firearms Laws, 26 U.S.C. §§ 5845, 5861

11. “Gun Show Loophole | EBSCO,” EBSCO Information Services, Inc. | www.ebsco.com, n.d., https://www.ebsco.com/research-starters/law/gun-show-loophole.

12. Chris Reitsma, “Texas Gun Laws,” Point Blank CHL, April 4, 2023, https://pointblankchl.com/texas-gun-laws/.

13. Giffords: Courage to Fight Gun Violence, “Trafficking Straw Purchasing Laws in Texas | Giffords,” GIFFORDS, April 29, 2024, https://giffords.org/lawcenter/state-laws/trafficking-straw-purchasing-in-texas/.

14. Giffords: Courage to Fight Gun Violence, “Gun Industry Immunity | GIFFORDS,” GIFFORDS, January 22, 2025, https://giffords.org/lawcenter/gun-laws/policy-areas/other-laws-policies/gun-industry-immunity/.

15. Wilson, Nick. “Mexico’s Lawsuit to Hold U.S. Gun Manufacturers Accountable Will Affect Public Safety in Both Countries.” Center for American Progress, April 8, 2025. https://www.americanprogress.org/article/mexicos-lawsuit-to-hold-u-s-gun-manufacturers-accountable-will-affect-public-safety-in-both-countries/. 

16. “Smith & Wesson Brands, Inc. V. Estados Unidos Mexicanos,” LII / Legal Information Institute, n.d., https://www.law.cornell.edu/supct/cert/23-1141.

17. “High Noon at the Supreme Court: Guns V. Mexico | Texas Law,” n.d., https://law.utexas.edu/faculty/publications/2025-high-noon-at-the-supreme-court-guns-v-mexico/.

18. Kalvis Golde, “Smith & Wesson Brands, Inc. V. Estados Unidos Mexicanos” SCOTUS Blog, April 7, 2025, https://www.scotusblog.com/case-files/cases/smith-wesson-brands-inc-v-estados-unidos-mexicanos/.

19. Abigail Geiger, “What the Data Says About Gun Deaths in the U.S.,” Pew Research Center, March 5, 2025, https://www.pewresearch.org/short-reads/2025/03/05/what-the-data-says-about-gun-deaths-in-the-us/.

20. Frank Newport, “American Public Opinion and Gun Violence,” Gallup.com, March 26, 2025, https://news.gallup.com/opinion/polling-matters/343649/american-public-opinion-gun-violence.aspx.

21. Duke Human Rights Center at the Franklin Humanities Institute, “Exit Wounds: Rights, Guns, and the Border,” March 12, 2025, https://humanrights.fhi.duke.edu/story/exit-wounds-rights-guns-and-border/.