Hunter Biden's ex-wife and a former girlfriend have testified at his criminal trial about finding his crack pipes and other drug paraphernalia.
And jurors have been shown photos of the president's son bare-chested in a bubble bath, and heard about his visit to a strip club, as he fights gun charges in a court in the US state of Delaware.
As the first lady sat in the front row, the courtroom grew quiet when Kathleen Buhle, who was married to Hunter Biden for 20 years, walked in.
She testified that she discovered her husband was using drugs when she found a crack pipe in an ashtray on their porch on July 3, 2015, a day after their anniversary.
When she confronted him, "he acknowledged smoking crack", she said.
The trial, about whether he lied on a gun purchase form in 2018 when he said he wasn't using drugs, has quickly become a highly personal and detailed tour of the mistakes and drug use of Hunter Biden. His struggles have been tabloid fodder for years and were used publicly by Republicans, including in their stalled impeachment effort against the president.
The proceedings are unfolding as the 2024 election looms, and allies worry about the toll it will take on President Joe Biden, who is deeply concerned about the health and sustained sobriety of his only living son.
Prosecutors argue the photos, testimony and other evidence are necessary to show Hunter Biden's state of mind when he bought the gun.
Hunter Biden has been charged with three felonies stemming from the purchase in October 2018.
He's accused of lying to a federally licensed gun dealer, making a false claim on the application by saying he was not a drug user and illegally having the gun for 11 days.
Jurors have seen the gun and the form at the centre of the case, and they have heard from the former clerk who sold the weapon.
The clerk, Gordon Cleveland, said he watched as Hunter Biden entered his name, address and other personal information on the form.
He said he was standing next to Hunter Biden when he began to answer a series of questions on the form with "yes or no" boxes to check.
Hunter Biden checked a box saying he was purchasing the gun for himself.
Another question asked whether the buyer was "an unlawful user of or addicted to" marijuana, stimulants, narcotics or any other controlled substance. "He wrote 'no'," Mr Cleveland said.
He also testified that Hunter Biden did not ask any questions or express any confusion about the question. He paid $US900 ($1,353) in cash, telling Mr Cleveland to keep the change — about $US13.
Ex-wife testifies about fear over drug habit
Prosecutors have hammered the idea that Hunter Biden was a habitual user, unable to stay clean for long.
Ms Buhle testified that even before she found the drugs, she suspected he was using. He had been kicked out of the Navy after testing positive for cocaine.
"I was definitely worried, scared," she said.
They have three children and divorced in 2016 after his infidelity and drug abuse became too much, according to her memoir, If We Break, about the dissolution of their marriage.
Ms Buhle, who was subpoenaed, was on the stand for 20 minutes.
She remained composed but seemed upset as she recounted how she searched his car about a dozen times for drugs, whenever the children were driving it.
"Did you ever see Hunter using drugs?" Hunter Biden's lawyer Abbe Lowell asked Ms Buhle.
"No," she replied.
Then, prosecutor Leo Wise asked Ms Buhle how she knew Hunter Biden was using drugs.
"He told me," she said.
Prosecutors also called Zoe Kestan, who testified under immunity about meeting Hunter Biden in December 2017 at a strip club in New York where she worked.
During a private session, he pulled out a pipe and began smoking what she assumed was crack.
"He was incredibly charming and charismatic and friendly, and I felt really safe around him," she said.
"I remember after he had smoked it, nothing had changed. He was the same charming person."
Ms Kestan detailed for jurors when she saw him use drugs, buy drugs, talk about drugs or possess drug paraphernalia.
Prosecutors asked her where he stored his drugs and pipes, and she testified he kept them in pouches and other places, such as sunglasses cases.
On cross-examination, Ms Kestan acknowledged that she had no contact with him in October 2018, the period when he bought the gun.
Jurors were shown dozens of pages of Hunter Biden's memoir, Beautiful Things, written in 2021 after he got sober.
And they heard lengthy audio excerpts from the book, which traces his descent into addiction following the death of his brother, Beau Biden, in 2015 from cancer.
The memoir covers the period he bought the gun, though it doesn't mention the weapon specifically.
Republicans try to tie son's behaviour to president
Mr Lowell has said Hunter Biden's state of mind was different when he wrote the book than when he purchased the gun, when he didn't believe he had an addiction.
He has also suggested Hunter Biden might have felt he had a drinking problem at the time, not a drug problem. Alcohol abuse doesn't preclude a gun purchase.
The Delaware trial comes after the collapse of a plea deal with prosecutors that would have resolved the gun case and a separate California tax case. He's now facing a separate trial in September on charges of failing to pay $US1.4 million in taxes.
Hunter Biden has since pleaded not guilty and has said he's being unfairly targeted by the Justice Department after Republicans slammed the now-defunct plea agreement as a sweetheart deal for the Democratic president's son.
In Congress, Republicans have for months pursued an impeachment inquiry seeking to tie the president to his son's business dealings.
So far, Republican politicians have failed to uncover evidence directly implicating the president in any wrongdoing.
But on Wednesday, local time, House Republicans accused Hunter Biden and the president's brother, James Biden, of making false statements to Congress as part of the inquiry.
At his criminal trial, Hunter Biden's personal messages have been shown as evidence, including some that came from a laptop he left at a Delaware repair shop and never retrieved.
In 2020, the contents made their way to Republicans and were publicly leaked, revealing some highly personal messages about his work and his life — some that appeared in congressional hearings. He has since sued over the leaked information.
Jurors are also expected to hear from James Biden, who is close with Hunter Biden and helped his nephew through rehab stints in the past. They will also get details on how Beau Biden's widow, Hallie Biden, became addicted to crack during a brief relationship with Hunter Biden after her husband's death.
Hallie Biden took the gun and tossed it into a rubbish bin at a nearby market, afraid of what he might do with it.
The weapon was later found by someone collecting cans and eventually turned over to police.
First lady Jill Biden went to court for the third consecutive day to support her stepson, ahead of her trip to France to meet the president, who was in Europe to mark the anniversary of D-Day.
If convicted, Hunter Biden faces up to 25 years in prison, though first-time offenders do not get anywhere near the maximum, and it's unclear whether the judge would give him time behind bars.
The trial is unfolding shortly after Donald Trump, the presumptive Republican presidential nominee, was convicted of 34 felonies in New York City.
The two criminal cases are unrelated, but their proximity underscores how the courts have taken centre stage during the 2024 campaign.
AP/ABC
