Will Illinois’ New Assault Weapons Ban Reduce Gun Violence?

Six months after a gunman legally purchased a semiautomatic rifle and killed seven people in Highland Park, a northern Chicago suburb, Illinois Governor J.B. Pritzker signed the Protect Illinois Communities Act into law, banning the sale and delivery of assault weapons, high-capacity magazines, and switches. Cook County enacted similar legislation nearly a decade ago, and the City of Chicago banned assault rifles in 2019. The bill is intended to reduce firearm access in all Illinois counties, including those with the highest rates of gun violence, such as St. Clair and Massac County. Gov. Pritzker says the bill is “the strongest and most effective gun violence legislation” Illinois policymakers have been able to achieve.

The key word in Pritzker’s reflection is “achievable,” because while this may be the strongest and most politically feasible legislation, it has glaring holes in redundancy, enforceability, and spillover which reduce its overall effectiveness. Research suggests it is likely the bill will reduce gun violence, but the critical questions are by how much, and whether we should settle for gun policy that is politically feasible rather than demonstrably effective.

Research Finds Assault Weapons Bans Reduce Mass Shootings

Illinois becomes the ninth state since 2004 to implement an assault weapons ban in the absence of any federal ban. Analyses of the narrowly focused federal assault weapons ban from 1994 to 2004 reveal important data on the effectiveness of such bans in reducing gun violence. The Giffords Law Center, a gun violence prevention organization, summarizes these findings:

• Assault rifles caused 85% of fatalities in public mass shootings resulting in four or more casualties.
• “During the 10-year period the federal assault weapons ban was in effect, mass shooting fatalities were 70% less likely to occur compared to the periods before and after the ban.”
• “In several major cities, the share of recovered crime guns that were assault weapons declined by at least 32% after the federal ban was adopted.”

In a Northwestern Medicine pre-print study, authors estimate the federal ban “prevented 10 public mass shootings during the decade it was in place.” They go on to estimate it would have further prevented “30 public mass shootings that killed 229 people and injured an additional 1,139 people” between 2004 and 2021.

While public health experts often argue in favor of assault weapons bans, it is important to note that minimal research exists on the statistical impact of such gun control measures. Further, some organizations such as Rand argue that existing research proves assault weapons bans only have  “uncertain” effects on mass shootings. This is partly due to the Dickey Amendment, a 1996 constitutional amendment championed by the National Rifle Association (NRA), that prohibits federal spending on research that could advocate for or promote gun control. Although Congress clarified the amendment’s scope in recent legislation, the almost 30-year ban on federal research makes it difficult to effectively analyze assault weapons bans. This is particularly true for understanding the impact of statewide bans.

A Redundant Regulation of Gun Modifications

Although these studies focus on reducing the number of assault weapons in circulation, a pernicious challenge to policymakers is regulating handgun modifications that give standard handguns semi-automatic properties. The Illinois assault weapons ban adds regulations to these modifications that are redundant to existing federal regulation. For example, the new Illinois law outlaws the “switch,” which “allows a conventional semi-automatic Glock pistol to function as a fully automatic firearm” (ATF). The illegal market for switches is pervasive in Illinois, as police seized over 300 from the streets of Chicago in 2020. During that same timeframe, South Side Weekly reported that “the number of extended magazines seized [in Chicago] nearly doubled” and “shootings involving them were twice as likely to have multiple victims as those without.”

On paper, the statewide ban reads as a solution to this increasingly pervasive market while ignoring the fact that switches have been illegal at the federal level for those without a license for years. Furthermore, a ban is only effective if it addresses the unregulated market, which it has failed to do. For many, notably those with existing or prior criminal charges, the preferred way to obtain a firearm is “off-book” transactions through personal networks. Therefore, the ban may not change the dynamics for an already illegal, relationships-driven market. Given that switches are already illegal, lawmakers and gun violence prevention advocates say the solution must also be federal, spearheaded by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

Enforceability: What Happens to the 30% and Why Does Now Matter?

In addition to concerns about the ban’s effectiveness at regulating the market for assault weapons and modifications, many are concerned about the ban’s enforcement mechanisms. Under the new law, owners must register current firearms with state police. At least 74 police departments across the state have signaled their refusal to enforce this process. Such refusal would leave an estimated 30% of the state out of the bill’s implementation. Failure to enforce the law could create conditions as dangerous as not having the ban. The recent mass shooting in Colorado Springs, Colorado is a tragic example where failure to enforce gun laws has serious implications. In that case, local police departments refused to confiscate the shooter’s weapons during a standoff with police a year prior to the 2022 massacre.

Yet, all policies have tradeoffs, and for most who oppose the bill, the principal concern is governmental infringement on the second amendment. Plaintiffs from at least 87 of Illinois’ 102 counties have already sued the state, building on the precedent set by the landmark 2022 case New York State Rifle and Pistol Association v. Bruen. Paul Clement, the attorney who argued in Bruen, will also serve as one of the plaintiffs to the federal lawsuit against Illinois’ legislation. In Bruen, the U.S. Supreme Court held a more conservative view of states’ rights to regulate individual gun ownership and expanded individual rights. Illinois gun owners will not be the first to justify their defiance of the recent assault weapons ban with Bruen, but the continued ambiguity in the Court’s decision will make the legal battle uncertain.

Further, citing Bruen for precedent has its own challenges, because the Court’s opinion itself is sufficiently vague. It has created less tangible legal precedent in one direction, but rather a larger legal ambiguity between the two political sides. Rand analysis suggests that Illinois legislators were just as likely to pass the assault weapons ban because Bruen pushed them to more extreme protection, just as conservative voters are driven to more extreme deregulation. This raises a critical point for the context of “achievability” referenced by Governor Pritzker; in this political environment where gun policy is under highly polarized scrutiny at the federal level, states are under heightened pressure to signal their positions, either by staking their ground in assault weapons bans or by loosening regulations. What is lost in the middle is a more meaningful conversation about the most effective approach to reduce gun violence by assault-style weapons.

Spillover: Buying Guns Across State Lines 

The greatest challenge to this bill’s ability to reduce gun violence is spillover, or its ability to regulate the manufacture, sale, and distribution of assault rifles beyond the Illinois border. ATF data from 2022 found that just under 50% of weapons in Chicago were purchased in Illinois – the others were purchased across the border in Indiana, Wisconsin, and the South. While the heightened criminal liability for possession may act as a deterrent, those who are determined will still be able to locate an assault weapon or extended magazine. This concern is articulated well by a participant in one of the University of Chicago Urban Labs’ Chicago Inmate Survey of Gun Access and Use: “As long as you can buy guns in Texas, Virginia, Indiana, or wherever…As long as you can buy twenty guns there and come back to Chicago and sell them, it’s going to happen” (86). A chilling example of spillover effects is Kyle Rittenhouse. In August 2020, Rittenhouse, an Illinois resident, purchased an assault-style weapon through a friend while in Wisconsin. He then used that weapon to kill two people and injure a third. A localized ban, therefore, is only as effective as it is matched by similar legislation across the nearest state line.

Implications for Current Legislation

The political constraints on gun legislation in today’s hyper-polarized environment only raises the stakes for gun policy. If gun rights advocates will continue to launch lawsuits against any perceived infringement on gun rights, it is critical that those working toward common sense legislation pass effective policies, knowing that each step forward may challenge any future policies.

Illinois’ new law is redundant and, in many ways, a settlement for what is achievable rather than effective. While we can celebrate that the ban may reduce some gun violence in Illinois, we should be aware of the challenges to its effectiveness:

First, the legislation fails to initiate a more substantive approach to regulating the illegal market for handgun modifications.

Second, a law is only as effective as it is well-implemented, and Illinois legislators will need to garner the support of at least 30% of state police agencies to enforce the bill if it is to reduce gun violence in all Illinois communities.

Third, even if the bill is enforced perfectly, it will still fail to prevent the spillover effect that enables individuals to buy guns in other states.

These critiques rest on two key facets of our political environment. First, the extreme federal polarization through the Supreme Court has increased pressure for tangible, but politically feasible policy change. Equally important to the political environment is the intentionally devastated information market on gun policy. The unfortunate truth undergirding any policy analysis of this bill is that the impact cannot be accurately assessed with a data-informed lens because the NRA and gun rights advocates have systematically prevented public health research on the effects of gun control.

Any reduction in the rising gun violence here in Illinois saves lives. However, we should not rest on this accomplishment and must continue to address the glaring holes in our statewide assault weapons ban to ensure solutions are both politically achievable and demonstrably effective.