In 2004, Rodney Vinson of Wendell hit his wife about the face with an open hand. He was charged and convicted of misdemeanor assault on a female.

Federal law stipulates that individuals previously convicted of a domestic violence crime may not possess firearms. So when police found a rifle and ammo tucked inside Vinson’s closet in 2013, the U.S. attorney for the Eastern District of North Carolina charged him with a federal crime.

Vinson fought the charge, arguing that hitting his wife wasn’t domestic violence, because it wasn’t violent per se—at least, not based on the confusing wording of the law. In December 2013, federal judge Louise Flanagan agreed with him and dismissed the indictment.

Now federal prosecutors are appealing Flanagan’s order, in attempt to keep the gun out of Vinson’s hands. Tomorrow in Richmond, a panel of judges for the Fourth Circuit Court of Appeals will hear oral arguments in U.S. v. Vinson. The case could have broad implications on American gun ownership and the definition of domestic violence.

In her order, Flanagan wrote that, under the law, assault and battery charges don’t necessarily connote acts of violence.

Take, for example, a stalker who shows up in a woman’s office and glares at her threateningly. Under North Carolina law, even though the act did not include violence, the stalker could be charged with assault, because he caused someone to fear for their immediate bodily harm.

Take, as another example, a boyfriend who gropes his girlfriend against her will. Under North Carolina law, even though the act did not include violence, he could be charged with battery, because he applied force, even if slight.

The U.S. attorneys prosecuting the Vinson case argue that, taken on face value, striking a woman with an open hand is clearly a violent act and should be treated as such.

In U.S. v. Castleman, considered by the U.S. Supreme Court a few months after Flanagan’s order, the justices ruled that “physical force” rather than “violent force” is sufficient to constitute domestic violence.

The Vinson case stems from a January 2013 incident in which Wendell police received information that Vinson allegedly threatened to kill his wife and children, and then fled. The police put on lock-down the elementary school in which Vinson’s children were enrolled. Mrs. Vinson permitted officers to search their home, where they discovered a Ruger .22 semiautomatic rifle, ammo and a 30-round magazine.