On December 2, the Supreme Court will hear Viramontes v. Cook County, where gun rights advocates are asking the justices to find that the Second Amendment protects the right to own AR-15s and similar assault weapons. At issue in the case are assault weapon bans first passed in the 1990s in Connecticut and in Cook County, Illinois. The Supreme Court has, for over a decade, declined to take action on all the assault weapons petitions before it, and against that backdrop of restraint, the number of states with assault weapons bans has grown to 11. But if the court decides this term that assault weapons are constitutionally protected, it will upend the status quo for everyone who lives under the protection of a state ban.
Over 118 million people — more than a third of the U.S. population — now live in a state where it is illegal to buy or own an AR-15. California, Connecticut, Delaware, Illinois, Massachusetts, Maryland, New York, New Jersey, and the District of Columbia ban the manufacture, sale, and possession of assault weapons. Rhode Island, Virginia, and Washington prohibit the manufacture and sale of assault weapons.
The Stalemate in Congress
Assault weapons used to be banned nationwide under the federal assault weapons ban of 1994, but Congress allowed that law to expire in 2004. Only five states — California, Connecticut, Massachusetts, New Jersey, and New York — prohibited AR-15s and other military-style firearms at the time the federal law lapsed. In the absence of federal and widespread state regulation, gun companies ramped up their production and sale of assault weapons with combat-ready features like pistol grips and collapsible stocks, and most of the AR-15s in circulation were made in the last 15 years. A House Oversight Committee investigation found that just five gun makers made over $1 billion selling AR-15-style assault weapons to civilians between 2012 and 2022. In March 2023, the Washington Post estimated that gun companies collectively earned over $11 billion selling such weapons in that time frame.
Mass shootings with assault weapons also occurred with horrifying frequency in the period after the federal law expired — in places like Orlando, San Bernardino, Las Vegas, Sutherland Springs, Parkland, Aurora, Pittsburgh, Buffalo, and Uvalde. Between 2016 and 2025, our nation saw one or more high-profile mass killings perpetrated with an assault weapon each year while American families buried hundreds of loved ones. An analysis of mass shootings during that time frame found that those involving assault weapons or high-capacity magazines resulted in four times as many people shot and twice as many people killed.
Yet when parents of children who were murdered in the mass shooting at Sandy Hook Elementary asked Congress to reinstate the federal assault weapons ban in 2013, many senators stonewalled them or made them tearfully pitch their case in the hallways of the Capitol. A federal policy that had bipartisan support in 1994 was killed by votes from both parties in 2013. Research suggests that had the federal assault weapons ban remained in place from 2004 to 2022, it would have prevented an estimated 38 public mass shootings, but for the past decade, Republican leaders in Congress have stalled bills that would ban military-style firearms.
States Fill the Void
State governments have poured millions of dollars into mass shooting emergency responses and healthcare for wounded victims, and many have legislated in their interests accordingly. Since 2012, six states have enacted laws banning assault weapons, and five states updated their laws to protect their constituents from the latest iterations of military-style firearms released to civilian consumers. In many states, the relationship between a mass shooting and legislation regulating assault weapons was made explicit. When Maryland Governor Martin O’Malley proposed a bill banning AR-15s just one month after the massacre of students at Sandy Hook Elementary, he said, “Perhaps there is no way to completely prevent the next Newtown tragedy, but then again perhaps there is. None of us can predict the future… And yet we know every life is valuable.”
The sentiment was similar when Delaware banned military-style assault weapons in 2023 following a horrifying summer of high-profile mass shootings. Delaware House Majority Leader Valerie Longhurst explained, “The intention of this legislation is simple and clear: To make sure the next Uvalde, the next Buffalo, the next Sandy Hook, does not take place in the state of Delaware.” At the time Delaware passed its law, 78 percent of state residents supported it. The oldest state bans on AR-15s in California, Connecticut, Massachusetts, New York, and New Jersey have similar origin stories: They were responses to the tragic mass shootings, like those that took place in Stockton, California, and at Columbine High School in Colorado.
While mass shooting survivors have made little headway in reinstating the federal assault weapons ban, many of them have been able to shape their state laws to make their visions of safety real in the places they call home. State assault weapons regulations are genuine expressions of a desire for safety and security put in place by lawmakers representing the grieving and the terrified. Even states that don’t currently prohibit assault weapons have joined with those that do to ask the Supreme Court not to limit their public safety powers.
Millions of people in this country currently live under the laws that many more of us want. A recent YouGov poll found that 63 percent of Americans support banning assault-style weapons. Americans of all stripes don’t want to live next to neighbors who own AR-15s. A majority of Pennsylvania voters support banning assault weapons, which their state law does not do. According to a recent Minnesota State Fair Poll, over 75 percent of respondents want to ban assault weapons in the state, but the Minnesota House Speaker refused to hold a floor vote on the issue in last year’s session.
The Future of Assault Weapon Laws
If the Supreme Court decides that laws like Connecticut’s and Cook County’s cannot stand, they will likely invalidate the responses of 11 states to perhaps the most salient and terrifying form of the American gun violence epidemic: mass-casualty events perpetrated with military-style firearms. That would consign us to a future where the people’s representatives cannot ban assault weapons like AR-15s, even if a shooter used one to kill dozens of their constituents in a single attack. This can’t be the picture of state’s rights, or local democracy, that the Supreme Court wants to paint.