A federal court will hear arguments dissecting the legal definitions of automatic weapons and determining whether an Orem inventor’s imprisonment for manufacturing machine guns should stand.

In 2015, U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives agents serving a search warrant in Kentucky found an illegal AR-15 assault rifle conversion kit and associated paperwork from an online sale.

That led them to a website registered to Scott Ray Bishop and linking to a video showing a masked man identified as “Nunya Bidnez” firing a semiautomatic rifle. The man inserted a small device into the gun and showed how it could then fire “on fully automatic.”

Bishop, 49, is now serving a 33-month federal prison sentence in Colorado for making and selling illegal machine guns via his kits.

But on May 9, the U.S. 10th Circuit Court of Appeals in Denver will hear Bishop’s appeal, which asserts District Judge Dee Benson in Salt Lake City violated his constitutional rights by not letting him testify about how his invention worked and what he intended it to do.

His attorneys, federal public defenders in Salt Lake, also are challenging ATF agents’ and federal prosecutors’ interpretations of firearms laws and whether Bishop’s device was illegal.

“Bishop’s testimony as to his belief, understanding, and intent were critical in light of the uncertainty regarding the definition of ‘automatic’ that ATF itself struggled with,” Bishop’s appeal team said in a document filed April 11 in Denver.

But Bishop, who represented himself at trial, was blocked from testifying about the intricacies of his device after prosecutors objected that he had not notified them of plans to offer expert testimony.

The appeal lawyers argue Bishop should not have been prevented from testifying about his device because his combined knowledge as a lay person and the inventor of the device was crucial for the jury to hear.

ATF definitions of “automatic” weapon function were “fluid” between 2008 and 2017, the appeal document said.

At the time ATF investigated Bishop’s device, ‘automatic’ was an ATF term of art with a fluid definition. Between 2008 and 2017, ATF provided different explanations for why certain bump-stock-type devices were not machine guns, but none of them extensively examined the meaning of ‘automatically.’

Bump stocks, such as that used by the Las Vegas mass shooter, were legal at the time Bishop was making his devices.

But on Dec. 18, 2018, the Justice Department amended ATF regulations to declare that “bump stocks fall within the definition of ‘machine gun’ under federal law, as such devices allow a shooter of a semiautomatic firearm to initiate a continuous firing cycle with a single pull of the trigger.”

And the ATF and prosecutors argued in Bishop’s trial that his device met the definition of illegal manufacture: one “intended to convert an ordinary gun into a machine gun — meaning, a gun that can fire automatically more than one shot, without manual reloading, by a single function of the trigger.”

Prosecutors also presented testimony from six customers who bought AR-15 conversion kits from Bishop and detailed efforts he took to avoid detection by authorities and falsely assure buyers the devices were not illegal.

Bishop said he designed the kit to “force reset” the trigger as the firearm was recycling between shots, thereby generating “a higher rate of fire” while still requiring “a separate pull of the trigger” for each round.

But one of his customers testified during the trial that the kit made his AR-15 function as an automatic. The man said he was “somewhat shocked at how easy it was and kind of scary. That rapid fire was — I have shot semiautomatics quite a bit and a full automatic is something entirely different.”

In February 2016, an undercover ATF agent contacted Bishop through a Utah gun exchange and arranged to buy an AR-15 from him.

They met in a dirt parking lot off Interstate 15 and the agent surreptitiously recorded their conversation.

The agent asked if Bishop knew anything about “modifications” “like full auto stuff.”

Bishop responded, “I’ve got a few of them,” and “I don’t have a problem telling people I’ve got full auto.”

Bishop told the agent that “it’s not legal,” but insisted that “I’m not one that is concerned about that.”

You can reach reporter Mark Shenefelt at mshenefelt@standard.net or 801 625-4224. Follow him on Twitter at @mshenefelt.

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