Federalism and Firearms: How Brazil and the United States Define the Limits of State and Local Authority
This guest post is based on a paper that was presented at the 2025 Firearms Law Works-In-Progress Conference and reflects the author’s views only. The Conference is held each year on a home-and-away basis with the University of Wyoming Firearms Research Center. This post also appears on the FRC's Forum.
When it comes to regulating firearms, both Brazil and the United States have federal systems with deeply polarized public debates. But the constitutional logic each country applies to firearms regulation, particularly at the local and state levels, is fundamentally different.
In the United States, the legal framework centers on the protection of individual rights. Since District of Columbia v. Heller, the Supreme Court has recognized an individual’s right to keep and bear arms for personal self-defense. That recognition was extended to state and local governments in McDonald v. City of Chicago, where the Supreme Court struck down a municipal handgun ban, holding that the right recognized in Heller applied to the states through the Fourteenth Amendment and limiting the ability of cities and states to ban firearms even under traditional zoning or police powers.
Years later, in Ezell v. City of Chicago (2011 and 2017), the Seventh Circuit confronted another version of this tension. Chicago required handgun permit applicants to complete range training, then effectively banned the operation of firing ranges within city limits. The court held that this regulatory contradiction violated Second Amendment. Rights, the court emphasized, are not just formal guarantees; they require access to the means necessary to exercise them.
This rights-based framework was reinforced in New York State Rifle & Pistol Association v. Bruen, where the Court invalidated New York’s “proper cause” requirement for concealed carry permits. Applying a historical-tradition test, the Court held that such a discretionary standard lacked historical grounding and therefore violated the Second Amendment.
These decisions show that, in the U.S., federal supremacy over firearms regulation is infrequently expressed through federal statutes. Rather, it is enforced through the Second Amendment. It binds all levels of government. Local and state regulations that burden that right, directly or indirectly, face serious constitutional constraints.
In Brazil, the picture is almost entirely reversed. There is no constitutional right to keep or bear arms. Instead, access to firearms is a legally regulated exception governed by federal law and presidential decrees. The Brazilian Constitution grants the Union exclusive authority over the commerce and regulation of arms and ammunition.
Law No. 10.826/2003 requires individuals to demonstrate “effective necessity” to obtain a firearm. That requirement bears some surface similarity to New York’s “proper cause” test, except that, in Brazil, it is required by federal law.
Between 2019 and 2022, under President Jair Bolsonaro, federal decrees lowered this standard by presuming that necessity was automatically satisfied in certain circumstances and by limiting administrative oversight. During this period, some states passed laws that also lowered this standard for hunters and sport shooters.
But in 2023, the Brazilian Supreme Federal Court declared these provisions unconstitutional. The Court held that “effective necessity” must be demonstrated through concrete, verifiable evidence. It also ruled that core regulatory standards, such as who may obtain a firearm and under what conditions, must be established by federal statute, not by executive decree or state laws.
Following that decision, and after a change in federal administration, new presidential decrees were issued in 2023 under President Luiz Inácio Lula da Silva. These created a new, uniform, and highly restrictive national framework.
Shooting ranges, for example, must be located at least one kilometer away from any school, may only operate between 6:00 p.m. and 10:00 p.m., and must follow strict safety and acoustic insulation rules. The new system also classifies sport shooters into three levels, each with specific training, competition, and acquisition requirements, similar to the Chicago ordinances struck down in Ezell.
Local backlash was not long in coming. In 2024, the municipality of Ribeirão Preto (São Paulo state) passed a law allowing shooting clubs to set their own hours and locations. The Brazilian Supreme Court promptly suspended the ordinance. It held that the subject was fully regulated by federal law and that municipalities lacked authority to create alternative rules, even under their general land use and zoning powers.
It’s interesting, however, that in 2023, the Court drew a different conclusion in a separate case involving the state of Paraná. There, a state decree required retired police officers to undergo psychological re-evaluation every five years, which was stricter than the federal rule that required evaluation every ten years. The Court upheld the state law, reasoning that states may supplement federal regulation in the interest of public safety, as long as they do not undermine it.
The contrast between these two decisions illustrates how Brazilian federalism treats firearms regulation. Supplementation is allowed, substitution is not. While local and state governments may add layers of oversight, they may not contradict or bypass the federal framework.
The Brazilian Supreme Court applies both ceiling and floor preemption models in firearms regulation. It enforces a ceiling by upholding the Union’s exclusive competence under Article 22, XXI of the Constitution, invalidating local laws that seek to relax federal standards. At the same time, it allows floor preemption by permitting states to adopt stricter rules, provided they reinforce rather than contradict federal law.
Although Brazil’s Constitution does not guarantee a right to possess firearms, it includes a provision that adds complexity to the regulatory model. Article 5, XI affirms that the home is the individual’s inviolable asylum. While this clause does not expressly mention firearms, it underscores a constitutional commitment to privacy and autonomy in the domestic sphere.
Requiring individuals to justify firearm possession within their homes may impose discretionary limits on a space the Constitution protects from state intrusion. The Supreme Federal Court has not directly addressed this potential conflict, but it reveals how regulation based on federal authority can produce constitutional friction when it enters the private domain.
This tension became more pronounced in light of Brazil’s 2005 national referendum on gun control. A majority of voters rejected a proposal to prohibit civilian sales of firearms and ammunition. The vote reflected broad societal resistance to outright prohibition. That public sentiment, favoring conditional access, stands in contrast to a regulatory framework that places wide discretion in the hands of the federal executive and imposes increasingly strict limits, even inside the home.
In conclusion, both systems impose real constraints on local and state governments, but they do so in radically different ways, reflecting distinct constitutional traditions and provisions.
Understanding that distinction helps clarify why a law in Chicago may be struck down as unconstitutional for violating the Second Amendment, while a similar law in Ribeirão Preto may be struck down for violating federal supremacy.