After a lengthy sidebar, overflow room cameras suddenly turned on to show prosecutors questioning a previous witness, FBI agent Erika Jensen, suggesting that the defense has rested its case and prosecutors are introducing a rebuttal case before the trial moves on to closing arguments.

If so, that would indicate that Hunter Biden did not testify in his own defense.

This morning's proceedings are underway.

Judge Maryellen Noreika began by reviewing with both parties motions by the defense to change proposed jury instructions.

The jury is expected to be brought back into court at 9 a.m. ET.

Hunter Biden has arrived at the courthouse for Day 6 of his federal gun trial, accompanied by his wife Melissa Cohen Biden.

First lady Jill Biden arrived shortly afterward.

President Joe Biden's brother James Biden and sister Valerie Biden also arrived.

The two waited outside until the court opened at 8 a.m. ET.

As the second week of Hunter Biden's gun trial gets underway this morning, defense attorneys will confront their most consequential decision: whether to put their client on the witness stand.

To allow Hunter Biden to testify in his own defense would carry myriad risks, as the president's son would likely face a grueling cross-examination from a prosecution team that has shows itself adept at eliciting testimony supporting their central contention in the case -- that Hunter Biden was addicted to drugs at the time he purchased the handgun at heart of the case.

Jurors witnessed that on Friday, when Naomi Biden, the 30-year-old daughter of Hunter Biden, struggled to explain text messages she sent her father in October 2018 after he had purchased the gun -- in which she seemed to express concern about his addiction, despite testifying moments earlier about how "great" her father seemed at the time.

If Hunter Biden decides not to take the stand, jurors could possibly have the case by the end of the day, after closing arguments and jury instructions.

Court is scheduled to get underway earlier than usual today, at 8:15 a.m. E.T.

Taking the stand as a prosecution witness, Hunter Biden's ex-wife Kathleen Buhle described how, after 25 years, their marriage deteriorated under the weight of his drug and alcohol addiction.

Buhle said she first learned of Hunter Biden's crack addiction when she discovered an empty crack pipe in an ash tray on their side porch the day after their anniversary in 2015. Hunter Biden was kicked out of the Navy in 2014 for testing positive for cocaine, and Buhle said ever since then she was "worried, scared" he would abuse drugs again.

When he was on crack, Buhle testified, "He was not himself … angry, short-tempered, acting in ways he wouldn't when he was sober."

She said she would find drug "remnants in little bags" and drug paraphernalia like "a broken crack pipe" -- often enough that she would search his car before allowing her daughters to use it.

In what could be a blow to one of Abbe Lowell's lines of defense, Buhle said Hunter Biden frequently interacted with friends and family, worked, and socialized while under the influence of crack cocaine -- and would often try to hide it from those close to him.

"Did you see him, for lack of a better word, function?" prosecutor Leo Wise asked.

"Yes," Buhle confirmed.