President-elect Donald Trump with Kansas Secretary of State Kris Kobach, who is up for a job in Trump's White House.

A Kansas man thought he found a legal way to sell his homemade firearms and suppressors out of his military surplus store, believing a state law protected him and his customers. Shane Cox even stamped “Made in Kansas” on them to assure buyers that the local law would prevent the federal government from bothering them about it, according to the Denver Post.

Business was brisk. The suppressors were flying out the door. One of Cox’s customers, Jeremy Kettler, was so excited about his suppressor, that he posted a video on Facebook about it.

But Cox and his customers had it a bit wrong.

Last week, a jury found Cox guilty of violating federal laws for the manufacture, sale, and possession of unregistered firearms and suppressors. Kettler was found guilty on one count for possessing an unregistered silencer, the story reports.

The case could reverberate across the country, since it cites the Second Amendment and pits the federal government’s right to regulate firearms against the rights of states, the story notes.

The state law in question says that firearms, accessories and ammunition manufactured and kept in Kansas are exempt from federal gun-control laws. The law also makes it a felony for the federal government to enforce federal laws. State lawmakers were informed the day after the law passed by then-U.S. Attorney General Eric Holder that it was unconstitutional.

Cox and Kettler were convicted under the National Firearms Act of 1934, which is part of the Internal Revenue code enacted under Congress’ power to levy taxes. The story says that the case raises the question of whether the act can be used to regulate firearms that stay within state borders. Advocates for state’s rights say such guns don’t fall under Congress’ control of interstate commerce.

From the story:

“Kettler told jurors he bought the unregistered silencer ‘because of a piece of paper signed by the governor saying it was legal.’ Before trial, he criticized Kansas for ‘setting up its citizens to be prosecuted’ by the federal government.”

The story says that legislators knew the law would cause disagreements on who has the authority to regulate firearms within the state.

“I think these gentlemen understood that when they made a choice to do what they did,” said Jim Howell, a former Republican state representative, in the story.

From the story:

“Kansas Attorney General Derek Schmidt has intervened to defend the state law’s constitutionality in the first criminal case that has used the Kansas law as a defense. Schmidt said in a statement that buyers’ reliance on the state law as a defense is ‘reasonable, and it is consistent with the State’s interest in ensuring the Second Amendment Protection Act itself is defended.’”

The Kansas law was modeled on the Montana Firearms Freedom Act, which the Court of Appeals for the Ninth Circuit has found to be invalid, the story points out. Similar laws have been signed in nine states, including Alaska, Arizona, Idaho, South Dakota, Tennessee, Utah, and Wyoming.

The man who helped write the Kansas gun law, Secretary of State Kris Kobach, is now a potential pick for a job in President-elect Donald Trump’s administration. In the story, Kobach called this case “a perfect example of a prosecution that should never occur.”