Hunter Biden's defense attorney, Abbe Lowell, seemed to telegraph a key element of his defense strategy in a Delaware federal court Friday about who exactly filled out the key federal gun form in question in the case.

The heart of the government’s case is Hunter Biden checking a box on a government form, specifically Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) form 4473, which stated he was not using or addicted to drugs at the time he was buying a gun.

There are two versions of the particular form that Biden filled out. The first was emailed Oct. 26, 2018, and U.S. District Court Judge Maryellen Noreika has allowed that form into evidence.

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Hunter Biden Capitol Hill

Hunter Biden is in court  (Tierney L. Cross/Bloomberg via Getty Images)

However, there is another version of the form — a physical version — that was filled out at a gun store. It was revealed in court Friday a gun store employee, Gordon Cleveland, helped Biden fill out the physical form that day. 

Cleveland is likely to be called to the stand, and Noreika suggested the government would likely ask him to testify that Biden filled out the form and signed it. 

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Hunter Biden crashes Oversight Committee

Hunter Biden (second from right), the son of President Biden, and his lawyer Abbe Lowell attend a House Oversight Committee meeting Jan. 10, 2024, in Washington, D.C.  (Kent Nishimura/Getty Images)

"We want to know who wrote what on the form," Lowell told the court.

Noreika asked him, "Is there evidence that [Biden] didn’t check the box?"

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An evidence photo shows Hunter Biden’s signature certifying he was eligible to purchase a gun

An evidence photo shows Hunter Biden’s signature certifying he was eligible to buy a gun in Wilmington, Del., Oct. 12, 2018.  (U.S. Department of Justice)

Lowell responded, "We now know that they tampered with that form. … Cleveland accepted an ID he shouldn’t have, and [Ron] Palmieri [the gun store owner] changed the form."

"What matters is what your client put on the form," said Judge Noreika.

Lowell again suggested it is all "subject to examination."

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Hunter Biden court sketch

A courtroom sketch depicting Hunter Biden in a federal courtroom in Wilmington, Del. July 26, 2023. (Courtesy William J. Hennessy, Jr.)

Noreika said she would rule later on whether the physical form would be allowed into evidence but seemed to agree that the gun store employees could be examined. 

"Why can’t he question his credibility?" she asked. 

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The trial will begin with jury selection June 3, and both sides agreed it would run until approximately June 14, or possibly into the next week.

As he left the courtroom, Hunter Biden, who wore tangerine-colored reading glasses at times during the proceeding, patted sketch artist Bill Hennessy on the back and asked, "How’s it coming?"