Jill Biden, wearing a purple blazer and scribbling on a white legal pad, sat in the first row of a drab fourth-floor courtroom on Monday, in a show of support for her son, Hunter, on the first day of his trial on federal firearms charges.
The first lady, who followed hours of mundane interviews with dozens of prospective jurors with rapt attention, rose to her feet when the judge called a short break about halfway through. She walked slowly over to her son, offered a long hug, then stroked his cheek.
The opening hours of jury selection in Mr. Biden’s trial on charges that he lied about his drug use in applying to buy a handgun in 2018 were, as expected, a high-stakes political spectacle — with a throng of reporters crowding the courthouse while TV crews did live shots, nearly nonstop, after sunrise.
But the presence of Mr. Biden’s family and friends, including his wife, Melissa Cohen Biden, his half sister, Ashley Biden, and his close friend Kevin Morris, served as a reminder that the trial was also a profound personal crisis for a family that has had more than its share of travails — in the middle of the most unforgiving presidential campaign in recent memory.
“Jill and I love our son, and we are so proud of the man he is today,” President Biden said in a statement issued after the proceeding began.
“Hunter’s resilience in the face of adversity and the strength he has brought to his recovery are inspiring to us,” added Mr. Biden, who spent Sunday night with his son at the family house in Wilmington. “Our family has been through a lot together, and Jill and I are going to continue to be there for Hunter and our family with our love and support.”
But the trial is also expected to air less flattering details of Hunter Biden’s family life.
The special counsel overseeing the prosecution, David C. Weiss, has signaled that he will call Hunter Biden’s former wife, Kathleen Buhle, who is locked in a long legal battle with him over unpaid alimony, according to prosecutors.
A top deputy to Mr. Weiss, Leo P. Wise, has filed court papers indicating that he also plans to call Hallie Biden, the widow of Hunter Biden’s brother, Beau. Ms. Biden was dating Hunter Biden when he bought the handgun at issue in the case.
By midafternoon, Judge Maryellen Noreika had selected 34 potential jurors, more than double the number needed to deliberate, including alternates.
Jury selection, which was on pace to wrap up over the next day or two, also provided an unexpected glimpse into the insular cultural and political microclimate of Delaware, one of the country’s smallest states, where encounters with the first family were so commonplace as to be almost unremarkable.
One potential juror, a former police officer, matter-of-factly told the judge that he had once worked with Dr. Biden at a local college. Just when it seemed he had passed muster, he let slip that he had supported Ferris Wharton, who unsuccessfully challenged Beau Biden for Delaware attorney general in 2006.
“Next juror, please,” Judge Noreika said, with a slight grin.
Last September, a federal grand jury charged Hunter Biden with three felonies: lying to a federally licensed gun dealer, making a false claim on the federal firearms application used to screen applicants and possessing an illegally obtained gun for 11 days, from Oct. 12 to Oct. 23, 2018.
If convicted, Mr. Biden could face up to 25 years in prison and $750,000 in fines. But nonviolent first-time offenders who have not been accused of using the weapon in another crime rarely get serious prison time for the charges.
Legal experts say it is more likely a sentence could include a central element of the original plea deal — mandatory enrollment in a firearms diversion program intended to reduce incarceration rates for the least serious gun crimes.
Mr. Biden, his legal team and his family are hoping to turn the court’s attention away from his actions during a long period of out-of-control drug and alcohol use to the more universal experiences of families affected by relatives with substance abuse problems, and Mr. Biden’s recent success in staying sober.
Many of the would-be jurors spoke emotionally about their own families’ struggles, with one man breaking down in tears when he talked about a brother-in-law who had been addicted to drugs.
Another juror candidate shared a relative’s history with substance abuse and how it had made her more sympathetic with other people experiencing similar problems.
“It’s a disease, and I don’t look down on that,” she said as Hunter and Jill Biden craned forward in their seats to listen intently. “People have problems.”
Mr. Biden has been sober for years and has written about his difficulty with crack addiction and alcohol dependency in his memoir, which is likely to be used as evidence. Over the past year, the president’s son has submitted to drug testing and passed, according to his lawyer Abbe Lowell.
The gun charges are related to whether Mr. Biden had lied on a standard form issued by the Bureau of Alcohol, Tobacco, Firearms and Explosives when he bought a .38-caliber pistol. Prosecutors said he falsely claimed he was not taking drugs at the time. Mr. Biden had the gun for under two weeks, he has said, before Hallie Biden tossed it in a dumpster, fearful that he would use it to harm himself.
It is relatively rare for such gun charges to be brought against a first-time, nonviolent offender like Mr. Biden, unless it is being used as leverage for a confession on other crimes, such as drug trafficking, current and former prosecutors have said.
The gun trial is only the first of two Mr. Biden is facing.
Last month, the federal judge in Los Angeles who is presiding over his tax case agreed to push the start of that trial from later this month to Sept. 5, giving Mr. Biden’s lawyers time to prepare.
While the move came as a relief to the president’s son, it thrusts into the homestretch of the campaign season a trial that is likely to highlight Hunter’s Biden’s efforts to leverage his family’s name into profit.
Mr. Biden has pleaded not guilty to charges of evading a tax assessment, failing to file and pay taxes, and filing a false or fraudulent tax return.
Judge Noreika, an appointee of President Donald J. Trump, tightly controlled her courtroom on Monday, much as she did during the hearing that ended Mr. Biden’s plea agreement last July, and showed every indication of wanting to move things along as quickly as possible.
She swatted down Mr. Lowell’s attempt to disqualify two potential jurors — hours after delivering two small but significant setbacks to Mr. Biden’s defense.
She has also ruled that Mr. Biden’s lawyers cannot refer to the fact that the local authorities declined to prosecute him when the gun was recovered. She also blocked Mr. Weiss from making any reference to the tax case when presenting evidence in Delaware.
For his part, Mr. Biden sat through the jury selection sternly, wearing reading glasses and taking notes.
But when the judge called for the midday break, he sprang from his seat like a student hearing the end-of-day bell, flashed a grin and began fist-bumping and hugging the people who had shown up to support him.
Zach Montague contributed reporting.