A Delaware jury found Hunter Biden guilty earlier this month on three federal charges stemming from his purchase of a handgun in 2018.

According to the Wall Street Journal, statements in a book the president's son wrote provided some of the evidence that was used against him. 

Federal law prohibits drug users from possessing firearms

Under federal law, anyone "who is an unlawful user of or addicted to any controlled substance" may not purchase or possess a firearm.

Yet in his 2022 memoir titled "Beautiful Things," Biden went into explicit detail about his frequent use of crack cocaine and other illegal substances around the time that he bought a Colt Cobra revolver.

Hunter Biden confronted his demons of addiction in his memoir, “Beautiful Things,” when it was released months after his father became president. The book came back to haunt him in court. https://t.co/qNFwXHsFIK https://t.co/qNFwXHsFIK

— The Wall Street Journal (@WSJ) June 18, 2024

The Journal noted that prosecutors played portions of the audio book version of "Beautiful Things" in which Biden could be heard reading out incriminating passages.

In a chapter called "Lost Highway," Biden admitted to illegal drug use after breaking up with Hallie Biden, the widow of his late brother Beau Biden.

Biden admitted to "doing nothing but drinking and drugging"

"I had returned that fall of 2018, after my most recent relapse in California, with the hope of getting clean through a new therapy and reconciling with Hallie. Neither happened," he wrote.

"For all the obvious reasons—my extended disappearances, my inability to stay sober, her need to stabilize and reorder her own life and family—Hallie and I called it quits," the president's son continued.

In chapters titled "California Odyssey" and "Saved," Biden recounted his heavy substance abuse while living on the West Coast.

After landing in Los Angeles, Biden's "first call off the plane was to a drug connection," after which he "was doing nothing but drinking and drugging."

Former prosecutor says Biden's book "blew up in his face"

The Journal noted that during his closing arguments, prosecutor Leo Wise made reference both to "Beautiful Things" along with text messages that Biden had sent.

"We also have his own words in his memoir describing buying and using drugs during that whole period from 2015 to 2019, four years, what he called four years of active addiction, and how he relapsed after numerous attempts at rehab," Wise declared.

Meanwhile, former federal prosecutor Michael Weinstein told the Journal that Biden's memoir "blew up in his face" as it contained "admissions from him and statements from his own mouth without his own counsels’ ability to water them down."