In Garland, Attorney Gen. v. Vanderstok, the Supreme Court will examine a Biden administration rule on ghost guns impacting manufacturers, sellers and buyers.Under federal law, gun parts are not considered firearms, so purchasing a kit online does not require a background check. The Biden law changed that, requiring checks and proof of age to buy. It also required manufacturers to put serial numbers on gun kits and obtain licenses to sell them.But gun rights groups and more than two dozen Republican states argue that the federal agency, the Bureau of Alcohol, Tobacco, Firearms and Explosives, overstepped Congress' authority in creating the law."The gun case will test how much the court is willing to disregard what agencies determine," George Washington University School of Law professor Alan Morrison said. "When these guns...come disassembled, they don't get a serial number put on them, so it's impossible for law enforcement to track these guns and find out where they came from. It's a big law enforcement problem."According to government data, the number of ghost guns soared before the regulation but has since flattened out.Morrison adds that the case has little to do with the Second Amendment. Instead, it deals with federal agency power, which has been a consistent theme among cases the Supreme Court has taken up.The conservative justices have shown deep skepticism over agencies having the power to regulate anything from the environment to consumer protections that Congress has not explicitly spelled out in law.But, the Court has been inconsistent when ruling on cases dealing with guns, striking down a Trump administration ban on bump stocks last term and leaving in place a rule taking guns from people with domestic violence-related restraining orders against them.In Garland, Attorney Gen. v. Vanderstok, the justices previously intervened, leaving the Biden rule intact while the case plays out. The Court likely will not issue a ruling until spring or early summer.