An Alameda County law effectively barring new gun stores is being challenged by Second Amendment advocates to the nation’s highest court.

The ban, which forbids gun retailers within 500 feet of residential properties thereby placing the whole county off-limits to new stores, is challenged by businessmen John Teixeira, Steve Nobriga and Gara Gamaza who found that the county’s zoning made it impossible to find commercial property.

The case, rebuffed by lower courts, is backed by a number of gun rights groups to include the California Association of Federal Firearms Licensees, the Calguns Foundation, and the Second Amendment Foundation, with attorneys Alan Gura and Don Kilmer at the helm.

“You simply cannot allow local governments to ignore the Second Amendment because they don’t like how the Supreme Court has ruled on the amendment twice in the past ten years,” said SAF founder Alan Gottlieb. “You shouldn’t be able to zone the Second Amendment out of the Bill of Rights.”

The original challenge dates back to 2012 after the men attempted over a two-year period to comply with the county and were initially granted a variance from the 500-foot rule to lease a location 446 feet away from a residential area. However, the Board of Supervisors reversed their decision after a local homeowners’ association who were “opposed to guns” objected, leading the entrepreneurs to seek redress with the courts.

While a District Court upheld the rule, a split three-judge panel of the U.S. 9th Circuit in 2016 found Alameda County’s regulations unconstitutional on Second Amendment grounds. The majority noted that county officials should provide evidence showing, for instance, that gun stores increase crime to justify such regulations. That decision, in turn, was vacated and the case sent for retrial before the larger en banc panel last year who held local governments could regulate the sale of firearms and that the Second Amendment does not protect the ability to engage in gun sales.