Hunter Biden's drug abuse has taken center stage in his criminal trial for buying an illegal firearm, with former partners of the president's son sharing lurid details about his crack addiction.

Biden's ex-wife Kathleen Buhle and a former girlfriend, Zoe Kestan, both shared accounts of Biden's constant crack consumption, with Buhle describing the moment she discovered her husband was abusing cocaine. 

“I found a crack pipe on July 3, 2015,” Buhle said, "in an ashtray on the side porch of our home.”

“I went looking for my husband and asked him what it was,” she said. “He said it was a crack pipe. He acknowledged smoking crack.”

Hunter's ex-wife testifies

Buhle said she had to be vigilant to protect her family, noting she would sometimes find drugs in Biden's car during regular sweeps of the vehicle.

Prosecutors have accused Biden of lying about his drug addiction when he purchased a revolver in 2018. Defense lawyers have argued that Biden was not actively using drugs at the time, telling the jury that his "high functioning" behavior proves that he was clean.

In his opening statement, defense lawyer Abbe Lowell told the jury that there is "no such thing as high-functioning crack addicts," but prosecutors have elicited testimony to the contrary.

Buhle said that Biden was "angry" and volatile when high, but she agreed with prosecutors that he could function more or less normally.

“I was worried, scared,” she said. “He was not himself. He was angry, short-tempered, acting in ways he hadn’t when he was sober.”

Biden "functioning" addict

Biden's ex-girlfriend Zoe Kestan told the jury that she witnessed Biden smoke crack "every 20 minutes" during one of his regular binges.

“I thought to myself, ‘It’s crazy his demeanor doesn’t seem to be changing,'” Kestan said. “I never saw an immediate change in his behavior, which really confused me.”

Another ex-lover of Biden's, his widowed sister-in-law Hallie Biden, told the jury that she "panicked" when she tossed Hunter's gun in a trash can.

She said her brother-in-law got her addicted to crack, describing it as a "terrible experience" that she regrets now.

“It was a terrible experience that I went through,” she added. “I’m embarrassed and ashamed, and I regret that period of my life.”

Hallie Biden also said Hunter could be both "high-strung" and "functioning" while on drugs.