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Rocky Mountain Gun Owners v. Polis


Representing the City of Boulder in defending Colorado’s prohibition on large-capacity magazines. The City and County of Denver jointly filed this amicus brief with the City of Boulder.

Court: Colorado Supreme Court

Issue at Stake: Large-capacity magazines

Summary: The City and County of Denver and the City of Boulder filed this amicus brief in the Colorado Supreme Court in defense of a Colorado statute prohibiting the possession of large-capacity magazines (LCMs). This brief explains how Denver’s and Boulder’s experiences as two of Colorado’s largest and most densely populated cities—both of which have enacted their own local LCM prohibitions to protect their citizenry—demonstrate that the state law is closely related to Colorado’s interests in public health, safety, and welfare, and thus constitutional under the state constitution. Examining the leading social science research, the brief explains that, consistent with Denver’s and Boulder’s experiences, the use of LCMs makes mass shootings and other gun violence incidents more dangerous and more deadly. And the brief also shows how, as the empirical data demonstrates, are not necessary, and rarely used, in self-defense—and how this aligns with the on-the-ground experiences and understanding of Denver and Boulder. Everytown Law represented the City of Boulder on this brief.

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