The U.S. Supreme Court on Monday vacated U.S. District Court Judge Reed O’Connor’s September decision blocking enforcement of the new rule covering so-called “ghost guns.”

The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) issued a new Final Rule unilaterally redefining incomplete pistol frames and parts as “firearms.” Under this new standard, the agency may mandate background checks for specific gun parts kits enjoyed by hobbyists by claiming they are actual firearms.

On July 2, O’Connor ruled in favor of the Firearms Policy Coalition, the Second Amendment Foundation, Jennifer VanDerStok and others. The judge determined the ATF overstepped its authority and ventured into legislative territory when it redefined “frame” or “receiver.”

Congress had yet to define these terms, so they default to their normal definitions.

This decision to vacate was upheld three weeks later by the Fifth Circuit Court of Appeals, but the agency’s fight continued. 

On Aug. 8, the Supreme Court allowed the “ghost gun” rule to stand, meaning the ATF’s Final Rule would be enforced as the appeals make their way through the Fifth Circuit.

O’Connor once again stepped up last month in defense of the Second Amendment and issued an injunction against the rule. However, on Monday SCOTUS issued an order setting this action aside. 

The high court’s decision affects two Texas-based manufacturers of gun kits, Blackhawk Manufacturing and Defense Distributed. These kits may be purchased online or at a retailer. 

For centuries, hobbyists have constructed their own firearms, and the practice is still going strong. The ATF’s new rule is just another phase in the battle to eradicate private gun rights.

The government argued that O’Connor’s decision to grant an injunction “openly flouted” the high court’s authority. However, plaintiffs believe he was correct in putting a roadblock in front of an unconstitutional overreach by the ATF.