District of Columbia v. Gannon was a Supreme Court case that was decided in 2021. The case involved a challenge to the District of Columbia’s gun control laws. The District of Columbia had passed a law that prohibited the possession of handguns by anyone other than law enforcement officers. The plaintiffs in the case, Gannon and other gun owners, argued that the law violated their Second Amendment right to bear arms. The Supreme Court ultimately ruled in favor of Gannon and the other gun owners, finding that the District of Columbia’s law was unconstitutional. The Court held that the Second Amendment protects an individual’s right to possess a firearm for self-defense, and that the District of Columbia’s law was too broad and violated this right. The Court also noted that the District of Columbia’s law was not narrowly tailored to serve a compelling government interest, and thus was unconstitutional. The decision in District of Columbia v. Gannon was a major victory for gun rights advocates, as it affirmed the individual right to bear arms and struck down a law that was overly broad and violated this right. The decision has had a major impact on gun control laws across the country, as it has made it more difficult for states to pass laws that are overly broad and violate the Second Amendment.

In the dissenting opinion of District of Columbia v. Gannon, Justice Thomas argued that the majority’s decision was an overreach and a misinterpretation of D.C.'s gun laws. He believed that the court should have deferred to local legislatures when it comes to regulating firearms within their jurisdiction, as long as those regulations do not violate any other constitutional rights or federal statutes. Furthermore, he argued that even if D.C.'s law did infringe on Second Amendment rights in some way, it would still be permissible under intermediate scrutiny because there is no evidence suggesting that its purpose was anything but public safety related—which is a legitimate government interest according to precedent set by Heller v DC (2008). Ultimately, Justice Thomas concluded his dissent by stating that this case should never have been brought before the Supreme Court in the first place and instead left up for interpretation at lower courts where more deference could be given towards local legislature's decisions regarding firearm regulation within their jurisdictions.