Hallie Biden, the widowed daughter-in-law of President Joe Biden, became romantically involved with Hunter Biden in the wake of the death of her late husband Beau Biden.

Hallie testified this week in federal court about certain aspects of her relationship with Hunter, in particular, his illicit drug use and crack cocaine addiction, as part of Hunter's ongoing trial over a trio of federal gun charges, according to a series of brief reports from NBC News.

Hunter is facing prosecution over false statements he made about his drug use on the federal gun purchase form he filled out to fraudulently purchase a revolver in 2018 that he knew he was prohibited from possessing because of his otherwise admitted addiction to and frequent illegal use of a federally controlled substance.

Hallie's knowledge of Hunter's drug use at the pertinent time

Per the NBC News reports, Hallie Biden was called to the witness stand on Thursday by the prosecution to, in exchange for an immunity agreement, testify about her intimate knowledge of Hunter Biden's illicit drug use and addiction to crack, which she sometimes smoked with him and would sometimes accompany him on drug deals.

Hunter would "occasionally" smoke crack in front of Hallie at her home in Wilmington, Delaware, where he would often leave paraphernalia around for her and her children to find, as well as at an apartment he rented in Washington D.C. and at a home they shared in Annapolis, Maryland.

She testified about how his demeanor would typically change while he was high on crack, how they frequently fought about his drug use, and how he eventually introduced her to smoking crack herself, which she described as "a terrible experience that I went through and I’m embarrassed and I’m ashamed of that period of my life."

The discovery and disposal of the gun; Hunter's habit of lying

NBC News reported that Hallie Biden also testified about finding Hunter Biden's illegally purchased revolver in his vehicle and how she disposed of it in a leather pouch in a trash can outside a nearby grocery store in Wilmington, where it was discovered by an elderly man searching for recyclables who subsequently turned it over to local police.

That incident sparked a huge fight between the couple over Hunter's drug use and gun ownership and eventually led to the end of their romantic relationship.

Under cross-examination by Hunter's defense lawyers, Hallie was unable to recall if she'd seen Hunter smoke crack during the brief period he illegally possessed the revolver he had obtained via false statements made on the required ATF Form 4473 about his illicit drug use.

She also admitted that Hunter often lied to her about his activities and whereabouts, which the defense lawyers seized upon to question the validity of text messages he'd sent her during the period in question that seemed to indicate that he was engaged in various illicit drug-related acts at the time.

Case previewed in trial briefs filed by prosecution and defense last month

While some of the particulars of Hallie Biden's testimony may have been a surprise to some the gist of what she would say had already been previewed by Special Counsel David Weiss in a trial brief submitted to the court last month that laid out the basic elements of the case and the prosecution's strategy, according to Law & Crime.

In addition to Hallie, the prosecution also noted that it intended to hear testimony from Hunter Biden's ex-wife, Kathleen Buhle, and another ex-girlfriend about their knowledge of his illicit drug use. The prosecution also planned to cite extensively from Hunter's own admissions of addiction and drug use in his autobiography as well as submit evidence of such in the form of pictures, videos and messages pulled from his infamous laptop and his iCloud account.

All of that and more will be used by the prosecutors in an attempt to prove that Hunter knowingly and willfully lied on the federal form about his drug use and addiction to illegally purchase a firearm he knew he was prohibited from possessing by federal law due to said illicit drug use and addiction.

The defense, meanwhile, also submitted a preview to the court of their intentions to raise certain Second Amendment-related arguments as well as claims that Hunter was confused by a purported lack of definitions and instructions on the ATF form and was unaware that he was prohibited from purchasing or possessing a gun.