Skip to content
Search

Latest Stories

Top Stories

Supreme Court wrestles with meaning of 'trigger' in bump stocks case

News

Supreme Court

The Supreme Court attempted to dissect the 1934 National Firearms Act’s definition of "machine gun" in oral arguments last week.

Alicia Tang

Tang and Elkowitz are undergraduate students at Northwestern University's Medill School of Journalism.

While much of the attention on the Supreme Court in recent days has focused on cases involving former President Donald Trump, the justices recently heard oral arguments on a subject that garnered national attention in 2017.

On Feb. 28, the court wrestled with how to interpret the National Firearms Act of 1934, which includes an ambiguous definition of “machine gun,” in a case to determine whether firearms with bump stocks should receive that classification.

The case involves bump stocks, which were used in the 2017 mass shooting in Las Vegas, are defined by the Bureau of Alcohol, Tobacco, Firearms and Explosives as “devices that allow a semiautomatic firearm to shoot more than one shot with a single pull of the trigger.” The two sides in Garland v. Cargill diverged in their definition of trigger.

“That's the language we're stuck with,” lamented Justice Brett Kavanaugh, acknowledging the law was originally passed as a direct response to gang violence during the Prohibition era.


A bump stock harnesses the recoil energy from the initial trigger of a firearm, allowing it to continuously shoot without active intervention after the first shot.

In 2002, the ATF deliberated over a particular bump stock known as the Akins Accelerator. The ATF determined that under the 1934 statute, the bureau could not regulate the Atkins Accelerator because it required repeated pulls of the trigger to fire multiple shots. However, in 2006, the ATF revisited its ruling and determined that bump stocks like the Atkins Accelerator were machine guns.

Since then, many different bump stocks have emerged, leading to several ATF rulings between 2008 and 2017 that excluded them from the machine guns designation. After the Las Vegas music festival shooting in which 60 people were killed, making it the deadliest mass shooting in U.S. history, the ATF under the Trump administration redefined bump stocks as machine guns. The decision exposed bump stock owners to criminal liability if they did not destroy or turn in the devices by March 26, 2019.

Michael Cargill, the owner of Central Texas Gun Works, challenged the ruling when it went into effect in 2019. A federal district court sided with the ATF, contending that the ruling abides by the best interpretation of the statute.

“The case is about whether or not the ATF have the authority to promulgate this rule, not whether or not it is constitutional under the Second Amendment to regulate bump stock,” Kelly Roskam, director of law and policy at the Johns Hopkins Center for Gun Violence Solutions, said in an interview with Medill News Service.

“Those weapons do exactly what Congress meant to prohibit when it enacted the prohibition on machine guns,” attorney Brian Fletcher argued before the Supreme Court on behalf of Attorney General Merrick Garland and the federal government.

Fletcher maintained that it would be “irresponsible” for the ATF to overlook its previous judgment that bump stocks were not machine guns in light of the Las Vegas shooting.

Cargill’s argument rested on the back-and-forth movement of the trigger between shots and the human intervention required to keep shooting. In contrast, Garland’s position hinged on the technicality that the shooter is no longer actively controlling the trigger after the first shot and thus is initiating a continuous cycle of fire.

The U.S. Appeals Court for the Fifth Circuit sided with Garland, judging that Congress willfully excluded trigger finger movement when constructing the statute. Cargill soon after appealed that decision to the Supreme Court.

“The trigger is the device that initiates the firing of the weapon. A bump stock does not change the trigger in any way,” Jonathan Mitchell, attorney for Cargill, said during oral arguments.

Justice Ketanji Brown Jackson doggedly questioned Mitchell, homing in on the intent of Congress.

“Why would Congress want to prohibit certain things based on whether the trigger is moving as opposed to certain things that can achieve this, you know, lethal kind of spray of bullets?” asked Jackson.

Both Jackson and Justice Elena Kagan maintained that though the mechanisms may differ, a semi-automatic gun equipped with a bump stock and a typical machine gun have the same capability.

“At some point, you have to apply a little bit of common sense to the way you read a statute and understand that what this statute comprehends is a weapon that fires a multitude of shots with a single human action,” said Kagan.

Mitchell, however, continued to insist upon a difference between the function of bump stocks and that of machine guns.

“It has a very high rate of fire, but it's not automatically fired,” replied Mitchell.

If the court rules in favor of the government, the ban on the ownership and transfer of bump stocks will remain in effect.

If the justices side with Cargill, Americans will be able to possess and purchase bump stocks unless Congress or state legislative bodies enacts new laws.

“The ATF doesn't have the power to make something a crime that wasn't a crime before. It's not a crime to violate the rule,” said Fletcher. “It has been and always will be a crime to violate the statute.”


Read More

The Pennsylvania state capitol building.

The Pennsylvania state capitol building.

jimfeng/Getty Images

Pennsylvania’s Bipartisan Exchange Is Rebuilding Trust in Governance

The University of Pittsburgh Institute of Politics has nearly 40 years of experience working with legislators from different political parties, and it is building on this history by drawing on lessons from the successful American Congressional Exchange model, begun in 2018 at the Bipartisan Policy Center, and from state exchanges now underway in Minnesota and Michigan. The University of Pittsburgh Institute of Politics, in collaboration with the Bridge Alliance, has launched the Pennsylvania Legislative Exchange.

This state-based, systematic approach is designed to foster better relationships and build trust across the political aisle with the following guiding principles:

Keep ReadingShow less
An empty grocery cart in a market.

NYC Mayor Zohran Mamdani proposes five city-run grocery stores. See the arguments for and against, from food deserts to bodega concerns and the $70M cost.

Getty Images, Kwangmoozaa

Government-Owned Grocery Stores: Accessible Nutrition or Government Overreach?

Issue Introduction

Over the past few years, affordability has become the most central issue affecting Americans and the quality of life in the United States. The prices of groceries and basic necessities have risen 25-30% since the COVID-19 pandemic and are projected to rise another 3.2% in 2026. At the same time, the exodus of grocery chains from rural and low-income areas has scattered food deserts throughout individual states. Recent mass closures include Grocery Outlet’s shuttering of 36 stores and continued shut-downs of many Albertsons locations. These factors have led politicians to make affordability a major campaign issue.

During his progressive campaign for mayor of New York City, Zohran Mamdani raised the idea of opening grocery stores owned and operated by the city government to provide New Yorkers with affordable groceries. In his April 2026 public address that marked his first 100 days in office, Mayor Mamdani announced plans for the first of five city-run grocery stores. Mamdani’s proposed initiative will use $70 million in capital funding to build five city-owned municipal stores–one in each borough–and place them under control of the New York City Economic Development Corporation (NYCEDC). NYCEDC will then select third-party operating staff in accordance with city standards for affordability and proper labor practices. Public opinion following the announcement continues to be divided between uproar and support.

Keep ReadingShow less
Five men sitting on one side of a table, as a panel at an event.

Harvard's Guy-Uriel Charles (left) listens to David Walker, Chair of the Federal Fiscal Sustainability Foundation. Fellow panelists (L-R) are Michael Farris, Convention of States Project; Samuel Fieldman, Wolf Pack; and Jim Rubens, FFSA and American Promise.

Photo by Martha Stewart

Congressional Inaction Raises Constitutional Change Alternative

Voting is the anchor of democracy, as we are reminded every two years. But this anchor rests on unstable ground today, signaling that our political roots need examining too.

In the United States, the Constitution itself becomes the focus when serious problems prompt such foundational civic dives. Our current challenges may not be as severe as the Civil War or the excesses of the Gilded Age, which produced waves of amendments, but today’s erosion of our system of checks and balances requires us to revisit our constitutional underpinnings.

Keep ReadingShow less
​U.S. Defense Secretary Pete Hegseth

U.S. Defense Secretary Pete Hegseth testifies during a Senate Committee on Appropriations hearing on Capitol Hill in Washington, D.C., on July 21, 2026. Hegseth is crafting a strong and masculine identity for his audience as he reportedly contemplates a presidential run.

(Alex Wroblewski/AFP/Getty Images/TNS)

Politicians Can’t Just ’Give the People What They Want’

For reasons that will baffle my many detractors, I am often asked for advice about being an opinion journalist. One of my standard responses is: You have to be willing to disappoint your biggest fans.

What I mean is that if you start to see your job as telling fans what they want to hear, you risk becoming an entertainer rather than a thinker, and eventually you become a caricature. I’ve seen it happen numerous times. Patrick Buchanan was a brilliant columnist and a serious person. But over the course of his career, he listened too much to the people who said, “Go Pat, go!” and too little to friends who said, “I think that’s taking it too far.”

Keep ReadingShow less