Skip to content

Are Lax US Gun Laws Spilling Violence into Mexico?

The question:

Do more guns cause more violence?

The experiment:

We exploit a natural experiment induced by the 2004 expiration of the U.S. federal assault weapons ban to examine how the subsequent exogenous increase in gun supply affected violence in Mexico. The expiration relaxed the permissiveness of gun sales in border states such as Texas and Arizona, but not California, which retained a pre-existing state-level ban.

The results:

Using data from mortality statistics and criminal prosecutions over 2002-2006, we show that homicides, gun-related homicides and gun-related crimes increased differentially in Mexican municipios located closer to Texas and Arizona ports of entry, relative to those nearer California ports.

Gun-related Homicides in Municipalities Bordering California versus Other Border States

Our estimates suggest that the U.S. policy change caused at least 158 additional deaths each year in the post-2004 period. Gun seizures also increase differentially, and solely for the gun category that includes assault weapons. The results are robust to controls for drug trafficking, policing, unauthorized immigration, and economic conditions in U.S. border ports, as well as drug interdiction efforts, trends by income and education, and military and legal enforcement efforts in Mexican municipios.

The conclusion:

Our findings suggest that U.S. gun laws have exerted an unanticipated spillover on gun supply in Mexico, and this increase in gun supply has contributed to rising violence south of the border.

From a paper presented by Oeindrila Dube at NYU’s Development Seminar, with Arindrajit Dube and Omar Garcia-Ponce.

 

This entry was posted in Academic research. Bookmark the permalink. Follow any comments here with the RSS feed for this post. Both comments and trackbacks are currently closed.

14 Comments

  1. Bill wrote:

    And how many deaths are due to the elephant standing squarely in the middle of the room? i.e. the war on drugs.

    Posted May 13, 2011 at 1:01 am | Permalink
  2. jimg9x21 wrote:

    Consider the unfettered flow of firearms from:
    1. Central and South America, with automatic weapons and military explosives.
    2. ATF supplying thousands of guns through their “Gunrunner” program.
    3. The Mexico military with thousands of deserters that change sides taking their US Government issued weapons with them.
    4. The drug cartels with wads of cash that can order weapons from anywhere in the world.
    Compare these facts to the demise of the “assault weapon” ban and I think you might come up with a more complete picture as to why there are more deaths in Mexico.
    I would also add that the Mexican Government that bans firearm ownership for law abiding Mexicans to defend themselves probably adds to the problem but more significantly, the Mexican Government’s inability to deal with the drug cartels is at the root of the problem.

    Posted May 13, 2011 at 8:14 am | Permalink
  3. @jimg9x21: These are good points if one is trying to understand the overall causes of all gun deaths in Mexico. The point of Dube’s paper is to use a natural experiment to identify the cause of some gun deaths in Mexico. Carefully identifying the cause of 158 deaths per year is important even if similar methods can’t be used to identify the other causes of other deaths that you rightly point out.

    Posted May 13, 2011 at 10:28 am | Permalink
  4. QT wrote:

    jimg9x21,

    Tend to agree that the research looks only at 2 variables and is by design very limited.
    Well has it been said that the design of a study can determine what one finds as well as what one wishes to find.

    Caveat emptor

    Posted May 13, 2011 at 12:29 pm | Permalink
  5. Dane wrote:

    @Bill Good point hmm…but any thoughts on how to operationalize a variable for the “war on drugs?” Do you think the study’s controls do a good enough job? Or should they be combined somehow into a single metric. Hierarchical factor score?

    @QT the research does not look at 2 variables, it looks at… “The results are robust to controls for drug trafficking, policing, unauthorized immigration, and economic conditions in U.S. border ports, as well as drug interdiction efforts, trends by income and education, and military and legal enforcement efforts in Mexican municipios” What other variables do you feel the researchers should have examined?

    @jimg9x21 how do the alternative explanations you point out explain why deaths would rise in border towns closer to AZ and TX, but not CA?

    I think this study sounds (I haven’t read the paper, yet) well done. But I might add that I’m skeptical of accurate crime/homicide statistics from Mexico. Not (just) because it’s Mexico, but because even crime statistics from the United States are notoriously unreliable.

    Posted May 13, 2011 at 12:38 pm | Permalink
  6. Derecho wrote:

    1. Central and South America, with automatic weapons and military explosives.
    2. ATF supplying thousands of guns through their “Gunrunner” program.
    3. The Mexico military with thousands of deserters that change sides taking their US Government issued weapons with them.
    4. The drug cartels with wads of cash that can order weapons from anywhere in the world.
    Compare these facts to the demise of the “assault weapon” ban and I think you might come up with a more complete picture as to why there are more deaths in Mexico.

    Totally agree!

    Posted May 13, 2011 at 11:57 pm | Permalink
  7. D. Watson wrote:

    What happened to non-gun violent deaths? As that paragon of economic wisdom, Archie Bunker, said, “Would it make you feel better if they was pushed outta windows?”

    Posted May 14, 2011 at 5:11 am | Permalink
  8. BornLib wrote:

    I find it odd how inconsistent these results are with crime trends in the US.

    Since they focused on Texas and Arizona, so will I.

    According to the FBI, Texas has seen a steady decline in the rate of violent crime in general (9%), and murder rates in particular (12%), from 2004 through 2009.

    Arizona has seen even more impressive reductions over the same span of time. While both the rate of violent crime in general, and murder rates in particular went up in 2005, over the span of 2004 to 2009, the rate of violent crime decreased 19% and the murder rate dropped by 25%.

    For comparison, the US national data over the same period showed a 7% drop in violent crime rates and a 9% drop in murder rates.

    Posted May 14, 2011 at 7:03 pm | Permalink
  9. BornLib wrote:

    “The question:”
    “Does gun ownership make you less safe?”

    “The experiment:”
    “Collating the latest homicide data available from the UN Office on Drugs and Crime with SAS [Small Arms Survey] data creates a dataset of 145 UN countries.”

    “The results:”
    “The graph below highlights the lack of correlation between GPC [guns per capita] and homicide rates (all rates in incidents per 100,000 population). Spearman’s value is -0.10: As GPC increases, homicide rates decrease, albeit weakly.”

    From:
    http://pajamasmedia.com/blog/united-nations-ignores-its-own-data-to-promote-gun-ban/?singlepage=true

    Posted May 14, 2011 at 7:32 pm | Permalink
  10. christian wrote:

    Do more guns cause more violence?

    Does the graph on gun-related homicides give any information to this question? I am not into this, but I do not think so. If one wants to commit a murder, he/she will substitute the better available firearms for poison & other weapons. That is obvious – but does the availability of guns indeed increase overall rates of murder/violence?

    The citation of the paper suggests that overall rate of homicides did also rise – ok, that would be an answer to the question. But the graph is not so interesting at all… or do I miss an important fact?

    Posted May 15, 2011 at 6:37 am | Permalink
  11. As much as I believe that U.S. guns are a real problem for Mexico, this article dramatically oversimplifies the story by:

    1) not explaining the other factors that played into the rise in violence in Mexican states bordering AZ and Texas (namely, conflicts among the Gulf, Juarez, Sinaloa and —more recently— Zeta drug trafficking organizations), and

    2) not using data through 2010 (which show that violence jumped suddenly in Baja California in 2008, and then fell just as suddenly in 2009… regardless of California’s gun laws).

    Posted May 17, 2011 at 11:46 pm | Permalink
  12. Careless wrote:

    Are people just unaware of what the “assault weapon ban” banned? It basically banned weapons that looked like military weapons. This wasn’t, say, a ban on machine guns and rocket launchers. The ability to purchase equally deadly weapons was retained while the bill was in effect.

    Posted May 20, 2011 at 1:30 pm | Permalink
  13. ElGaboGringo wrote:

    A couple items that may have a larger impact than gun laws:

    - California built a fence a while back, so coyotes and traficantes increasingly moved to Arizona, New Mexico, & Texas the last decade.

    - I believe there was a power vacuum created when one cartel fell, the war was over there territory in the middle, with violence centered there.

    Posted May 25, 2011 at 12:13 am | Permalink
  14. Mr. Econotarian wrote:

    The paper says:

    “DHS data gives the number of illegal immigrants apprehended in each border patrol sector”

    It should probably be kept in mind that the DHS does not catch every illegal immigrant, and the rate that it does (and how changes in border patrol operations affect the caught vs. uncaught rate as coyote tactics change) are likely to be highly variable.

    There is a constant state of flux of illegal immigrant population, for example there has recently been a large effort to deport criminal illegal immigrants:

    “In fiscal year (FY) 2010, U.S. Immigration and Customs Enforcement (ICE) removed more illegal aliens than in any other period in the history of our nation. ICE removed more than 392,000 illegal aliens-half of them, more than 195,000-were convicted of crimes, including murder, sex offenses and drug violations.”

    Moreover, it is believed that the financial crisis decreased the number of people seeking to enter the US illegally.

    Posted May 26, 2011 at 3:05 am | Permalink

3 Trackbacks

  1. [...] Link to the original site Filed in Aid by Mark Oppenneer SHARE THIS Twitter Facebook Delicious StumbleUpon E-mail « US Should Boost Trade With Poorest Countries » How Do Aid Agencies Deal with Wicked Problems? No Comments Yet [...]

  2. [...] Go here to see the original: Are Lax US Gun Laws Spilling Violence into Mexico? [...]

  3. [...] 2004, violence in Mexican states bordering US states with lax gun control laws (Texas and Arizona) has increased.  Second, US drug policies are inconsistent and counterproductive.  For a good discussion on the [...]