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."

In dramatic testimony, Hunter Biden's former romantic partner Hallie Biden described how, on the morning of Oct. 23, 2018, she went to go "clean out" Hunter Biden's car and found a gun.

"What did you find, in addition to trash and clothes?" prosecutor Leo Wise asked her.

"Remnants of crack cocaine and some paraphernalia," Hallie recounted. "Oh and the gun, obviously."

Hallie Biden said she found the firearm in "the arm console" of the car, which she said was not locked because "the lock had been broken." She said it was the first time she had ever seen a gun. She also found ammunition.

"I panicked, I wanted to get rid of them," she told the jury.

Asked why she panicked, Hallie Biden said she "didn't want him to hurt himself." She said she also worried about her kids finding the gun, saying she considered "hiding" it somewhere but was worried they would find it.

She said those frantic moments led to her throwing the gun in the trash. She told the jury she found a pouch to put it in -- which authorities say later tested positive for having cocaine on it -- and put the gun inside. The jurors were then shown the brown pouch she used.

"I was afraid to kind of touch it, I didn't know if it was loaded," Hallie Biden said, telling jurors she then put the pouch into another bag.

"I took it to the grocery store up the road and I threw it away," she testified.

At this point, jurors were shown surveillance video from the grocery store showing Hallie Biden throwing the gun into the trash.

In the video, her car is seen pulling into the parking lot; she then gets out of the driver's seated, opens the back door to get out the gun, then walks over to the store and places the bag in a garbage receptacle.

"Is that you Mrs. Biden?" prosecutor Leo Wise asked about her image on the video. "Yes," she replied.

Hunter Biden, sitting at the defense table, appeared to be locked on Hallie Biden the entire time, his head resting in his hand. He periodically covered his mouth.

Hunter Biden's former romantic partner Hallie Biden told jurors that Hunter Biden was "tired, exhausted, and looked like he hadn't slept" on the evening of Oct. 22 or early morning of Oct. 23, 2018, when he arrived at her home in Wilmington to sleep.

She observed that he "could've been" on drugs when she saw him -- just hours before she found his newly purchased Colt Cobra revolver in his car and discarded it in a dumpster.

"I went to clean out his car and his stuff" as he slept in her home, in hopes that when he awoke they could "start anew and deal with stuff," she testified, referring to his addiction to "both" drugs and alcohol.

The testimony didn't appear to be quite the smoking gun sought by prosecutors, who are trying to prove Hunter Biden was using crack at the time of his firearm purchase on Oct. 12 -- one of the central questions in the case.

Hallie Biden, who is the widow of Hunter Biden's late brother Beau Biden, testified that earlier in 2018 she also became addicted to crack after Hunter Biden introduced her to the drug -- but that she is now clean.

"It was a terrible experience I went through," she said, adding that she was "embarrassed and ashamed, and I regret that period of my life."