WILMINGTON, Del.—Prosecutors called Hallie Biden to testify on June 6, the fourth day of Hunter Biden’s federal gun trial, and she detailed their romantic relationship, their alleged drug use, and messages purportedly showing that Mr. Biden was using drugs around the time he bought the firearm.
Ms. Biden is the widow of Mr. Biden’s deceased brother, Beau, who died from cancer in 2015. Mr. Biden previously said he succumbed to crack cocaine addiction after his brother’s death, and he began seeing his sister-in-law romantically around the same time.