Hunter Biden's sister-in-law has testified at his trial that she took and threw away his gun out of fear of his spiralling addiction, potentially bolstering prosecutors' case that he broke a law barring illegal drug users from owning firearms.
Jurors in the first criminal trial of a US president's son saw surveillance camera footage of Hallie Biden putting Hunter Biden's gun in a supermarket bin, as well as texts where she said she feared for his life.
"Check yourself into a local rehab hunter, this has all got to stop," Hallie Biden wrote in an October 2018 text shortly after Hunter Biden bought the gun.
He has pleaded not guilty to three charges of failing to disclose his use of illegal drugs when he bought the Colt Cobra revolver and of illegally possessing the weapon for 11 days, until Ms Biden took it.
The jury has heard testimony this week from witnesses, including his ex-wife and a former girlfriend, about the 54-year-old's prolific drug use in the past, which he has publicly acknowledged.
Much of the earlier testimony and evidence covered periods before and after he had the gun, and the defence has tried to show that he had gone through drug treatment and could have considered himself sober when he bought the weapon in October 2018.
Defence attorney Abbe Lowell told the jury, during opening arguments on Tuesday, that there was no intent to deceive by Hunter Biden.
Hallie Biden, the widow of Beau Biden, who died of cancer in 2015, was the first witness to fill in details about Hunter Biden's behaviour when he possessed the gun.
She testified that she often cleaned out Hunter Biden's truck, searching for drugs, in an attempt to help him get his life in order.
She told the jury that she discovered drug paraphernalia and the gun during one of those searches, and feared Hunter Biden or her children would find the weapon and hurt themselves.
"I panicked and wanted to get rid of it," said Hallie Biden, adding that she struck up a romantic relationship with Hunter Biden beginning in late 2015 or early 2016.
She said that he introduced her to crack and she became addicted until she got clean in August 2018.
"It was a terrible experience I went through and I'm embarrassed and ashamed," she told the jury.
During cross-examination, Mr Lowell sought to show jurors that things Hunter Biden said about his drug use to Hallie Biden could not be taken at face value because he sometimes lied to her.
Hunter Biden told the judge in the case at a 2023 hearing that he had been sober since 2019.
Federal prosecutor Derek Hines said the government could call its last witness today.
Hunter Biden and his attorneys have not said if he will testify in his own defence, a risky move that most criminal defendants avoid because they expose themselves to questions from prosecutors.
If convicted on all charges, he faces up to 25 years in prison, though defendants generally receive shorter sentences, according to the US Justice Department.
The trial in Wilmington, Delaware, federal court follows another historic first - last week's criminal conviction of Donald Trump, the first US president to be found guilty of a crime.
Mr Trump is the Republican challenger to Joe Biden, a Democrat, in the 5 November election.
