Judge Maryellen Noreika, in her initial instructions to jurors, explained how they are to apply the law to the facts of the case for the three criminal counts Hunter Biden faces.

"You must not attach any significance to the fact that the defendant did not testify," she read aloud in the courtroom, after the defense decided not to call Hunter Biden to the stand.

The judge defined "knowingly," the central term by which jurors must determine if Hunter Biden bought the gun at the center of the case "knowing" he was an addict or user of drugs, after he stated on the gun-purchase form that he was not.

Closing arguments are scheduled to begin at 12:05 p.m. ET, after which the judge will give the jury her final instructions and their deliberations will begin.

Closing arguments will begin at about noon ET after Hunter Biden chose not to testify in his federal gun case.

The defense rested without him taking the stand, after which prosecutors presented a brief rebuttal case, then the judge gave the jury their initial instructions.

Following the prosecution's rebuttal case, the judge read the jury their initial instructions.

Court is then expected to break for lunch, with closing arguments currently scheduled for the afternoon.

The judge will then give the jury their final instructions before they begin deliberations.

The government rested its rebuttal case after a brief cross-examination of FBI special agent Erika Jensen, who testified about location and text message data relevant to the case.

Attorneys then gathered for another sidebar conference.

Jason Turner, an employee at the gun shop that sold Hunter Biden the Colt revolver at the center of the case, corroborated on the stand clerk Gordon Cleveland's earlier testimony of the sequence of events that occurred in the store when Hunter Biden filled out the ATF form and purchased the gun.

Turner, who appeared defensive and confrontational during some of his testimony, testified that he never spoke to Hunter Biden.

When shown the ATF Form 4473 that Hunter Biden filled out, Turner said Hunter Biden provided his car registration as an alternate form of ID because the passport he provided did not have an address.

The defense said in court papers filed earlier that confusion over how Hunter Biden's form of ID was recorded on the ATF form raised questions about "who wrote what on the form, and when."

When defense attorney Abbe Lowell, questioning Turner, highlighted the box on the form that asks for the type of alternate ID, it was blank.

"When I wrote that out, I wrote 'car registration,'" Turner said. "It's not there," he testified.

Lowell also pressed Turner on what he was doing after Hunter Biden's background check came back until the firearm was purchased.

"I would have put on my ritual tone and sat in a marble room," Turner said sarcastically.

Ron Palmieri, the owner of the gun store, then took the stand.