BELLEVUE, Wash. – The Second Amendment Foundation has filed a lawsuit in Denver County District Court challenging Colorado’s Proposition KK as an unconstitutional tax on the exercise of a fundamental constitutional right.
Joining SAF in Langston v. Humphreys are the National Rifle Association, Firearms Policy Coalition, Magnum Shooting Center of Colorado Springs, the Colorado State Shooting Association, and Zachary Langston, a private citizen. They are represented by attorneys David H. Thompson, Peter A. Patterson, William V. Bergstrom, Athanasia O. Livas, Julian R. Ellis, Jr., and Michael Francisco.
Heidi Humphreys, executive director of the state Department of Revenue, and Michael J. Allen, district attorney of El Paso County, are named as defendants in their official capacities.
Background on the Colorado Excise Tax Lawsuit
On March 31, 2025, a coalition of gun rights advocates—including the National Rifle Association (NRA), Second Amendment Foundation (SAF), FPC, and others—filed a lawsuit in Colorado state court challenging the constitutionality of a new 6.5% excise tax on firearms, ammunition, and firearm precursor parts.
This tax was created by Proposition KK, a ballot measure approved by voters in the November 2024 election. It is set to take effect on April 1, 2025, and is intended to fund mental health services, school safety, and support for victims of violence.
The plaintiffs argue the tax violates the Second Amendment by imposing a financial burden specifically on the exercise of the right to keep and bear arms. They cite U.S. Supreme Court precedent stating that constitutional rights cannot be singled out for special taxation. The complaint also challenges associated regulatory burdens—such as strict record-keeping, mandatory registration, and criminal penalties for non-compliance.
The lawsuit seeks a declaratory judgment that the tax is unconstitutional and a permanent injunction to prevent its enforcement.
Second Amendment Foundation and its partners contend that the state’s 6.5% excise tax on the retail sale of any firearm, firearm precursor part, or ammunition is unconstitutional in that it impermissibly singles out the exercise of a constitutional right for special taxation.
There have been several rulings by the U.S. Supreme Court prohibiting such a tax scheme.
“Colorado’s new law impermissibly taxes an enumerated constitutional right,” said SAF Executive Director Adam Kraut. “Not only does the tax lack any basis in our nation’s history and tradition of firearms regulation, it violates Supreme Court precedent that states the exercise of constitutional rights cannot be targeted through taxation. We look forward to vindicating the rights of all Coloradans who are affected by this egregious attempt to chill the exercise of Second Amendment rights.”
“Federal legislation to prevent this sort of tax was introduced just days ago in both the House and Senate,” noted SAF founder and Executive Vice President Alan M. Gottlieb. “They’re calling it the Freedom from Unfair Gun Taxes Act, and greedy, anti-gun lawmakers in Colorado are probably at least partly responsible for such a bill on Capitol Hill. You simply cannot tax the exercise of a constitutionally-protected fundamental right.”
For more information, visit saf.org.
SAF Wins Challenge to Pennsylvania Carry Ban for Young Adults
Effort to End New York’s Ban on Carry in Parks Merits Briefing at 2nd Circuit Court of Appeals
About Second Amendment Foundation
The Second Amendment Foundation (saf.org) is the nation’s oldest and largest tax-exempt education, research, publishing and legal action group dedicated to safeguarding and promoting the fundamental rights of individuals enshrined in the Second Amendment of the United States Constitution. SAF engages in aggressive legal action to ensure the principles of armed self-defense, personal liberty, and the ownership of arms are defended, secured, and restored. Through public education initiatives, SAF teaches the importance of the Second Amendment to promote a society that values and exercises the right to keep and bear arms.
This amounts to a double taxation by a bunch of crooks !
An EXCISE TAX?
Have you forgotten that there IS ALREADY a Federal EXCISE TAX of 10% when you buy a gun OR ammunition?! This “TAX” IS SUPPOSED to go to GUN RANGES and FORRESTRY and/or WETLANDS for our American FAUNA (wildlife and foul)!!
SO, these NAZIS are trying to add ANOTHER TAX upon a CONSTITUTIONALLY ACKNOWLEDGED RIGHT! VOTE THESE NAZIS OUT!!!
This is an important story, so I’d suggest editing the title. SAF “filed” a major lawsuit. They didn’t “drop” one. I was going into this article wondering why they would drop (cease) a major lawsuit for gun rights.
I wonder what this would mean for the Pittman-Robertson Act, if they win. After all, that’s a tax on our 2nd Amendment rights too.
ohh fun a poll tax by another name
It’s about time #2A organizations team up & put up a united fight!!! Not knocking what SAF has done historically one bit! But standing alone gets tiresome.