Case Information: Rocky Mountain Gun Owners v. Polis, No. 2018SC0817 (Colo. S. Ct. brief filed Aug. 12, 2019)

At Issue: The plaintiff in this case brings a state constitutional challenge to Colorado’s law prohibiting the possession, sale, or transfer of ammunition magazines holding more than 15 rounds— like those used in mass shootings from Sandy Hook to Las Vegas to Parkland and countless other tragedies. Going beyond than the law at issue, the challengers also urge Colorado’s highest court to abandon the judicial test Colorado courts have applied for two decades to gun regulations challenged under the Colorado constitution. That test, known as the “reasonable exercise” test, empowers legislatures to regulate guns to protect the public health, safety, and welfare; plaintiffs’ counter-proposal would force judges to severely limit the state’s traditional authority to protect residents from gun violence.

Giffords Law Center’s Brief: Our brief argues that the Colorado Supreme Court should uphold the challenged large-capacity magazine regulation under the reasonable exercise test, which historically more than 40 states have used in state constitutional challenges to gun safety laws. We argue that this test is appropriate because gun safety is a matter of state interest and concern, and the reasonable exercise test acknowledges Colorado’s essential role of protecting its citizens with firearm regulations tailored to the state’s unique experiences. Giffords Law Center’s brief argues that under the applicable test, Colorado’s magazine restrictions survive constitutional review because the law is carefully designed to reduce the number of mass shooting victims: large-capacity magazines (LCMs) are used in nearly 50% of mass shootings; all mass shootings in Colorado over the last 50 years involved LCMs; and, when LCMs are used in mass shootings, 40% more victims die, more than twice as many victims are shot, and the number of gunshot wounds per victim increases substantially.

Read the full text of our amicus brief here.