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Fact Sheet

Assault Weapons and High-Capacity Magazines Must Be Banned

Assault weapons and high-capacity ammunition magazines are weapons of war that have no place in America’s communities and should be banned.

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A sign calling for a ban on assault weapons is held at a vigil in Los Angeles for the Pulse nightclub shooting, June 2016. (Getty/David McNew)
A sign calling for a ban on assault weapons is held at a vigil in Los Angeles for the Pulse nightclub shooting, June 2016. (Getty/David McNew)

Gun Violence Prevention FAQs

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This fact sheet contains updates.

Assault weapons and high-capacity magazines have repeatedly been used to commit some of the worst mass shootings in modern U.S. history, and they contribute to the daily toll of gun violence in communities around the country. They are weapons of war that have no place in civilian society. Congress must enact a federal ban on assault weapons and high-capacity magazines to keep these dangerous weapons out of U.S. communities.

What is an assault weapon?

Assault weapons are semi-automatic firearms—meaning that they fire a round every time the trigger is pulled—that are capable of accepting a detachable magazine and have another military-style feature such as a pistol grip, a folding stock, or a threaded barrel. Firearm manufacturers, in response to declining sales of handguns, began selling assault rifles in the civilian market in the 1980s as part of a broader effort to create a new market for military-style guns among civilian gun owners.1

What is a high-capacity magazine?

A high-capacity magazine—also referred to as a large-capacity magazine—is a device that feeds ammunition into a firearm that holds more than 10 rounds of ammunition. A gun fitted with a high-capacity magazine can fire a higher number of bullets before needing to be reloaded. Today, models exist that can hold 20, 30, 50, or 100 rounds of ammunition in a single magazine. The functionality of high-capacity magazines has advanced in recent years, with the firearms and ammunition industry designing the devices to reduce the probability that ammunition will jam while multiple rounds are rapidly fired.2 Magazines that accept more than 10 rounds of ammunition can be used in both long guns and handguns that accept detachable magazines.3

What happens when an assault weapon with a high-capacity magazine is used in a shooting?

When assault weapons were used, six times more people were shot compared with those incidents in which other firearms were used.

The use of an assault weapon equipped with a high-capacity magazine increases the likelihood that a particular shooting will have a high death and injury count. These weapons are designed to fire bullets at higher velocities than handguns, increasing the lethality of shootings perpetrated with them.4 An analysis of mass shootings committed from 2009 through 2018 found that when assault weapons were used, six times* more people were shot compared with those incidents in which other firearms were used. Similarly, when high-capacity magazines were used, five times* more people were shot compared with those mass shootings with no high-capacity magazines.5

What is the current federal law regarding assault weapons and high-capacity magazines?

There are currently no restrictions in federal law on the manufacture, sale, and possession of assault weapons and high-capacity magazines. In 1994, a federal ban was enacted on assault weapons and high-capacity magazines as part of the Violent Crime Control and Law Enforcement Act,6 but it was allowed to expire in 2004.

Do any states ban assault weapons and high-capacity magazines?

Currently, seven states and Washington, D.C.7 have laws banning assault weapons, while nine states and Washington, D.C. ban high-capacity magazines.8 Yet these state-level efforts are undermined by the lack of a strong federal law banning these weapons. In July 2019, for example, a shooter shot 15 people, killing 3, in Gilroy, California, using an assault rifle purchased in Nevada. Although this firearm was banned and unavailable for sale in California, it was easily available in Nevada, which does not have a state-level assault weapons ban.9

Do bans on assault weapons and high-capacity magazines work?

A growing body of research finds that the federal assault weapons ban—though only in effect for 10 years—had a positive impact on reducing both the use of assault weapons in crimes and the numbers of firearm injuries and fatalities in mass shootings:

  • In 2004, the U.S. Department of Justice found that following the implementation of the ban, a number of cities and jurisdictions reported declines in the number of assault weapons recovered from crime scenes. These declines ranged from 17 percent to 72 percent.10
  • Researchers analyzing public mass shootings from 1982 through 2011 found that both state and federal bans on assault weapons resulted in decreased rates of mass shooting fatalities. The federal ban also indicated a decrease in rates of mass shooting injuries.11
[D]uring the 10-year period the federal ban was in effect, mass shooting fatalities were 70 percent less likely to occur than either before or after the ban.
  • A 2019 study examined mass shootings from 1981 through 2017 and analyzed the risk of fatalities in those incidents. The study found that during the 10-year period the federal ban was in effect, mass shooting fatalities were 70 percent less likely to occur than either before or after the ban.12
  • Research from Stanford University reviewed U.S. mass shootings13 over a 35-year period. The analysis found that the decade during which the federal assault weapons ban was in effect was linked to a 25 percent decrease in mass shootings and a 40 percent decrease in mass shooting deaths.14 Additionally, the research found that in the decade after the ban expired, mass shooting deaths increased by 347 percent.*15

The ban on high-capacity magazines within the federal assault weapons ban also had an impact:

  • A Washington Post investigation of the impact of the federal ban in Virginia found that during the years it was in effect, there was a noted decline in the number of guns equipped with high-capacity magazines recovered from crime scenes; the rate reached a low of 10 percent in 2004. After the ban expired, this rate increased, reaching 20 percent in 2010.16
  • A 2019 study analyzing mass shootings17 that were committed between 1990 and 2017 found that 77 percent of mass shootings perpetrated with a high-capacity magazine occurred in states that did not have state-level bans on these specific ammunition-feeding devices.*18
RIP written on the sidewalk in chalk at the memorial for the shooting victims outside of Tops market on May 20, 2022 in Buffalo, New York

Ban Assault Weapons in Our Communities

Assault weapons and high-capacity magazines have no place in civilian society. Tell Congress to act immediately to keep these dangerous weapons out of U.S. communities.

What happened when the federal ban expired?

Following the expiration of the ban in 2004, assault weapons and high-capacity magazines once again became legal to manufacture and purchase, and the gun industry responded with renewed fervor, flooding the civilian consumer market with these guns. Since the expiration of the federal ban, assault weapons and high-capacity magazines have been used to perpetrate some of the deadliest public mass shootings in modern U.S. history:

  • On August 3, 2019, in El Paso, Texas, 46 people were shot, 22 fatally.19
  • On February 14, 2018, in Parkland, Florida, 34 people were shot, 17 fatally.20
  • On November 5, 2017, in Sutherland Springs, Texas, 46 people were shot, 26 fatally.21
  • On October 1, 2017, in Las Vegas, 480 people were shot, 58 fatally.22
  • On June 12, 2016, in Orlando, Florida, 102 people were shot, 49 fatally.23
  • On December 14, 2012, in Newtown, Connecticut, 28 people were shot, 26 fatally.24
  • On July 20, 2012, in Aurora, Colorado, 70 people were shot, 12 fatally.25

Not only do these highly dangerous firearms and accessories continue to be used in horrific mass-casualty shootings, they are increasingly being used in cities that experience high rates of gun violence. A 2017 study found that guns equipped with high-capacity magazines made up between 22 percent and 36 percent of crime guns in the United States.26 A 2010 report from the Police Executive Research Forum noted that more than one-third of U.S. police agencies reported increased use of assault weapons following the expiration of the federal ban.27 In 2018, Baltimore Interim Police Commissioner Gary Tuggle stated that one-third of guns recovered in criminal investigations were equipped with high-capacity magazines. The Baltimore Police Department recovered 890 firearms with high-capacity magazines from January 1, 2017, through April 29, 2018.28

The ban’s expiration has also been linked to changes in international firearms trafficking. Assault weapons and high-capacity magazines are desirable weapons for organized crime and cartels in Mexico.29 A 2013 study found that following the expiration of the ban, Mexican municipalities bordering Texas, Arizona, and New Mexico reported increased levels of gun homicides. Municipalities near California did not see similar increases, likely due in part to the state-level ban on assault weapons.30

*Author’s note: This fact sheet will be periodically updated to account for new policy developments. It was last updated on February 10, 2021.


  1. Violence Policy Center, “The Militarization of the U.S. Civilian Firearms Market” (Washington: 2011), available at http://vpc.org/studies/militarization.pdf.
  2. Alain Stephens, “The Gun Industry Is Betting on Bigger High-Capacity Magazines,” The Trace, June 12, 2019, available at https://www.thetrace.org/2019/06/gun-industry-high-capacity-magazine-size/.
  3. Giffords Law Center, “Large Capacity Magazines,” available at https://lawcenter.giffords.org/gun-laws/policy-areas/hardware-ammunition/large-capacity-magazines/ (last accessed August 2019).
  4. Elizerie de Jager, Eric Goralnick, and Justin C. McCarty, “Lethality of Civilian Active Shooter Incidents With and Without Semiautomatic Rifles in the United States,” Journal of the American Medical Association 320 (10) (2018): 1034–1035, available at https://jamanetwork.com/journals/jama/fullarticle/2702134.
  5. Everytown for Gun Safety, “Ten Years of Mass Shootings in the United States: An Everytown for Gun Safety Support Fund Analysis” (New York: 2019), available at https://maps.everytownresearch.org/massshootingsreports/mass-shootings-in-america-2009-2019/.
  6. Public Safety and Recreational Firearms Use Protection Act, within the Violent Crime Control and Law Enforcement Act of 1994, H.R. 3355, 103rd Cong., 1st sess. (October 26, 1993), available at https://www.congress.gov/bill/103rd-congress/house-bill/3355.
  7. California, Connecticut, Hawaii, Maryland, Massachusetts, New Jersey, and New York are the only states with legislation banning some form of assault weapons. Giffords Law Center, “Assault Weapons: Summary of State Law,” available at https://lawcenter.giffords.org/gun-laws/policy-areas/hardware-ammunition/assault-weapons/#state (last accessed August 2019).
  8. California, Colorado, Connecticut, Hawaii, Maryland, Massachusetts, New Jersey, New York, and Vermont are the only states with legislation banning high-capacity magazines. Giffords Law Center, “Large Capacity Magazines: Summary of State Law,” available at https://lawcenter.giffords.org/gun-laws/policy-areas/hardware-ammunition/large-capacity-magazines/#state (last accessed August 2019).
  9. Dan Simon, Eric Levenson, and Darran Simon, “Assault-style rifle used in Gilroy shooting could not be sold in California, state attorney general says,” CNN, July 29, 2019, available at https://www.cnn.com/2019/07/29/us/gilroy-california-food-festival-shooting-monday/index.html
  10. The study examined Baltimore; Miami; Milwaukee; Boston; St. Louis; and Anchorage, Alaska. Christopher S. Koper, “Updated Assessment on the Federal Assault Weapons Ban: Impacts on Gun Markets and Gun Violence, 1994-2003” (Washington: U.S. Department of Justice, 2004), available at https://www.ncjrs.gov/pdffiles1/nij/grants/204431.pdf.
  11. Mark Gius, “The Impact of State and Federal Assault Weapons Bans on Public Mass Shootings,” Applied Economics Letters 22 (4) (2014): 281–284, available at http://www.tandfonline.com/doi/abs/10.1080/13504851.2014.939367.
  12. Charles DiMaggio and others, “Changes in U.S. mass shooting deaths associated with the 1994-2004 federal assault weapons ban,” Journal of Trauma and Acute Care Surgery 86 (1) (2019): 11–19, available at https://www.ncbi.nlm.nih.gov/pubmed/30188421.
  13. The researchers defined a mass shooting as an incident in which a shooter killed six or more people in a public setting.
  14. John Donohue and Theodora Boulouta, “That Assault Weapon Ban? It Really Did Work,” The New York Times, September 4, 2019, available at https://www.nytimes.com/2019/09/04/opinion/assault-weapon-ban.html.
  15. Ibid.
  16. David Fallis, “Data indicate drop in high-capacity magazines during federal gun ban,” The Washington Post, January 10, 2013, available at https://www.washingtonpost.com/investigations/data-point-to-drop-in-high-capacity-magazines-during-federal-gun-ban/2013/01/10/d56d3bb6-4b91-11e2-a6a6-aabac85e8036_story.html.
  17. The researchers defined a mass shooting as an incident in which a shooter killed six or more people.
  18. Louis Klarevas, Andrew Conner, and David Hemenway, “The Effect of Large-Capacity Magazine Bans on High-Fatality Mass Shootings, 1990–2017,” American Journal of Public Health (2019): e1–e8, available at https://ajph.aphapublications.org/doi/10.2105/AJPH.2019.305311.
  19. Chas Danner, “Everything we know about the El Paso Walmart massacre,” New York Magazine Intelligencer, August 5, 2019, available at http://nymag.com/intelligencer/2019/08/everything-we-know-about-the-el-paso-walmart-shooting.html.
  20. Evan Perez, “Florida school shooter could have fired many more bullets,” CNN, February 27, 2018, available at https://www.cnn.com/2018/02/27/us/florida-school-shooter-ammunition-left/index.html.
  21. Matt Pearce and John Savage, “26 dead in Texas church shooting, with children among the victims,” Los Angeles Times, November 5, 2017, available at https://www.latimes.com/nation/nationnow/la-na-texas-church-shooting-20171105-htmlstory.html.
  22. The New York Times, “Multiple weapons found in Las Vegas gunman’s hotel room,” October 2, 2017, available at https://www.nytimes.com/2017/10/02/us/las-vegas-shooting.html.
  23. Bart Jansen, “Weapons gunman used in Orlando shooting are high-capacity, common,” USA Today, June 14, 2016, available at https://www.usatoday.com/story/news/2016/06/14/guns-used-kill-49-orlando-high-capacity-common-weapons/85887260.
  24. Steve Almasy, “Newtown shooter’s guns: what we know,” CNN, December 19, 2012, available at https://www.cnn.com/2012/12/18/us/connecticut-lanza-guns/index.html.
  25. Dan Frosch and Kirk Johnson, “Gunman kills 12 in Colorado, reviving gun debate,” The New York Times, July 20, 2012, available at https://www.nytimes.com/2012/07/21/us/shooting-at-colorado-theater-showing-batman-movie.html.
  26. Christopher Koper and others, “Criminal Use of Assault Weapons and High-Capacity Semiautomatic Firearms: an Updated Examination of Local and National Sources,” Journal of Urban Health 95 (3) (2018): 313–321, available at https://link.springer.com/article/10.1007/s11524-017-0205-7.
  27. Police Executive Research Forum, “Guns and Crime: Breaking New Ground by Focusing on the Local Impact” (Washington: 2010), available at http://www.policeforum.org/assets/docs/Critical_Issues_Series/guns%20and%20crime%20-%20breaking%20new%20ground%20by%20focusing%20on%20the%20local%20impact%202010.pdf.
  28. Police Executive Research Forum, “Reducing Gun Violence: What Works, and What Can Be Done Now” (Washington: 2019), available at https://www.policeforum.org/assets/reducinggunviolence.pdf.
  29. Colby Goodman and Michel Marizco, “U.S. Firearms Trafficking to Mexico: New Data and Insights Illuminate Key Trends and Challenges,” in Eric L. Olson, David A. Shirk, and Andrew Selee, eds., Shared Responsibility: U.S.-Mexico Policy Options for Confronting Organized Crime (Washington: Woodrow Wilson International Institute for Scholars Mexico Institute and San Diego: University of San Diego Trans-Border Institute, 2010), available at http://www.wilsoncenter.org/sites/default/files/Shared%20Responsibility%2012.22.10.pdf.
  30. Arindrajit Dube, Oeindrila Dube, and Omar García-Ponce, “Cross-Border Spillover: U.S. Gun Laws and Violence in Mexico,” American Political Science Review 107 (3) (2013): 397–417, available at http://odube.net/papers/Cross_border_spillover.pdf.

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Explore The Series

In this fact sheet series, the Center for American Progress will answer some of the most frequently asked questions about key policy issues related to gun violence prevention. With an average of 106 people killed with a gun every day and thousands more suffering the lifelong impact of gun violence, it is more urgent than ever for policymakers to take action to address this public health epidemic.


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