Attorneys with the Second Amendment Foundation submitted a lawsuit last week asserting that the Colorado tax on firearms and ammunition is an unconstitutional tax on an inalienable right.

Colorado authorities now impose a 6.5% excise tax on the retail sale of “any firearm, firearm precursor part, or ammunition,” according to the lawsuit, which noted the “effects of the tax will be felt by all citizens of Colorado who elect to exercise their constitutional right to keep and bear arms as vendors pass the cost of the tax on to ordinary individuals who purchase firearms.”

The lawsuit, in which two local gun organizations, Firearms Policy Coalition, and the National Rifle Association are also plaintiffs, labeled the policy an “infringement-by-taxation scheme.”