Delaware state trooper Joshua Marley, testifying for the prosecution, described his role in investigating a report of a "stolen gun" on Oct. 23, 2018.

He said that at the time that he believed Hunter Biden "was the victim of the crime."

The gun turned out to have been discarded by Hallie Biden after she discovered it in her then-boyfriend Hunter Biden's car.

Marley spent only a short time on the stand before stepping down.

The government has four witnesses left before resting its case, meaning they will likely continue into Friday morning.

Defense attorney Abbe Lowell continued to probe Hallie Biden's memory of the period in 2018 when she discovered the gun purchased by then-boyfriend Hunter Biden, at one point remarking that there are "some things you remember and other things you don't."

She testified that for most of the month of October 2018 she did not see Hunter Biden abusing alcohol or drugs.

She also said that in the period after she disposed of the gun and filed a police report, her relationship with Hunter was "more tense."

When her testimony concluded, she stepped off the stand.

The government next called Delaware State Police officer Joshua Marley as its next witness.

Under cross-examination from defense attorney Abbe Lowell, Hunter Biden's former girlfriend Hallie Biden said some of her memories of their interactions from the time of the gun purchase are vague.

Lowell began his questioning by saying he understood that it was a "fairly upsetting" period and that "being here is no picnic either."

Hallie Biden conceded that "it's difficult to recall" exactly where Hunter was at specific moments or whether he was where he suggested he was, at one point saying that "it's all kind of vague."

"Reconstructing this is not easy?" Lowell asked her.

"Correct," she replied.

Hallie Biden, the widow of Hunter Biden's late brother Beau Biden, testified that the "remnants" of crack she found in Hunter Biden's car on Oct. 23, 2018 -- the day she discovered then discarded the firearm -- could have been from weeks or months earlier.

"You didn't see him doing drugs or alcohol" the day you discarded the gun, Lowell inquired.

"Correct," she said.

At one point Lowell's cross-examination descended into a bit of chaos as both Lowell and Hallie Biden struggled to follow the proper protocols to get her text messages admitted into evidence.

"So far so good," Abbe said at one point.

"Well, no," prosecutor Leo Wise objected.

Jurors rubbed their eyes and gazed around as the back-and-forth continued, with the courtroom bursting into laughter on several occasions. At one point, Hallie Biden appeared to look over at her fiancé sitting in gallery, shrugging her shoulders and appearing to mouth the words "I don't know."

Court was subsequently recessed for lunch.

Prosecutor Leo Wise read through text messages Hunter Biden's then-girlfriend Hallie Biden exchanged with him in the days following his gun purchase and on the day that she discovered and discarded it, asking her on the stand to provide context for their communications.

Within days of buying the gun, Hunter Biden texted her that he was about to meet a drug dealer named "Mookie." Hallie Biden testified that she thought that to mean "that he was buying crack cocaine."

In another message, Hunter Biden wrote that he was "buy" and then seconds later added "ing." Asked how she interpreted that message, Hallie Biden said, "I mean, I would guess but I didn't know for sure."

In the messages, Hallie Biden repeatedly expressed concern for him, at one point saying explicitly that she didn't want him to die. Wise asked her if she was worried that he would overdose on drugs.

She said "Yes," but added that she was also worried he might die by "suicide, I didn't know."

Wise then asked her to describe the messages the two exchanged on the morning she threw the gun away.

"It's hard to believe anyone is that stupid," Hunter Biden wrote to her.

"He was angry with me" for discarding his gun and putting him in legal jeopardy, Hallie Biden told jurors.

"I'm a liar and a thief and a blamer and a user and I'm delusional and an addict," Hunter Biden texted her.

She texted back, "Let's do this right," and suggested "working on sobriety" together.

Asked what she meant by "sobriety" -- alcohol or drugs or both -- Hallie Biden replied, "Well, if you're sober, it's all of the above."

Attorneys for Hunter Biden, in their cross-examination of FBI Special Agent Erika Jensen, attempted to push back on prosecutors' contention that Hunter Biden was abusing drugs at the time he said on a gun-purchase form that he was drug-free.

A key piece of evidence comes from Hunter Biden's 2021 memoir, in which he described his "relapse" just weeks after leaving rehab in August -- just six weeks before purchasing the firearm.

"I stayed clean for two weeks then relapsed," Hunter Biden wrote in his book.

Defense attorney Abbe Lowell, on cross-examination, questioned the assumption that Hunter Biden's relapse implied that he was referring to his drug use -- suggesting instead that he was referring to his alcohol addiction.

"When he was referring to that in his book, was he talking about relapsing to drugs and alcohol, or do you know what he meant?" Lowell asked.

"I can only state what was stated," Jensen said.

"Which is, 'Then I relapsed?'" Lowell asked.

"Just what it says, 'I relapsed,'" Jensen replied.

Jensen also acknowledged that she could not verify that Hunter Biden was continuously using drugs from 2015 to 2019, saying, "My recollection is that there are excerpts where he was principally occupied with smoking crack cocaine. I didn't get the sense that it was the entire history."

"Meaning that there were periods of time that he was not?" Lowell asked.

"I think there -- including the period in August where we have some invoices for rehab, that there were periods where there was not," Jensen said.

It was an important moment for the defense, as Lowell managed to establish that Hunter Biden's use of drugs was not consistent -- cuing up his argument that the president's son was not on drugs at the time of his firearm purchase.

Prosecutors also entered into evidence records related to enormous cash withdrawals Hunter Biden made -- more than $150,000 from September through November of 2018, including a $5,000 withdrawal on the day he purchased the gun. Prosecutors suggested this cash was used to procure drugs; Lowell, on cross-examination, established that Hunter Biden paid $900 in cash for the weapon and accessories.

Court was subsequently recessed for the day, with Lowell's cross-examination of Jensen scheduled to resume Wednesday morning.

Prosecutors suggested that Hallie Biden would be the next witness after Jensen, making it likely that the first Biden family member to testify will take the stand at some point tomorrow.