Chemist Jason Brewer, testifying as an expert witness for the prosecution, told the jury that a brown leather pouch that contained Hunter Biden's gun at the time the weapon was retrieved by authorities tested positive for cocaine.

Brewer said there were "minimal amounts of white powder" on two locations on the pouch, which he combined and tested.

On cross-examination, Hunter Biden's attorney sought to raise doubts about how that white powder got there and who put it there -- emphasizing it could have been old, dating back to before Hunter Biden purchased the gun.

"You can't date when it got there?" defense attorney David Kolansky asked.

"I cannot," Brewer said.

Kolansky also emphasized that five years went by from the time the pouch was collected in October 2018 to when it was tested in October 2023 -- after the indictment in this case was already filed.

He emphasized the importance of the "chain of command," which Brewer conceded was "very important."

Earlier, Hunter Biden's former girlfriend Hallie Biden testified that she put the gun in the pouch, which she found in Hunter Biden's vehicle, after she discovered the weapon in the vehicle and before she disposed of it in a trash container.

Proceedings resumed this morning with the government calling FBI chemist Dr. Jason Brewer to the stand.

Brewer is testifying as an expert witness.

Prosecutors said they would then call a DEA officer as their final witness.

First lady Jill Biden, Hunter Biden's stepmother, is in attendance at the trial this morning.

She returned from France, where she was accompanying President Joe Biden on a trip to mark the 80th anniversary of D-Day.

She had attended the trial each day until making the trip to France.

Hunter Biden has arrived at the courthouse for Day 5 of the trial.

He was accompanied as usual by his wife Melissa Cohen Biden.

Hunter Biden's former romantic partner Hallie Biden told jurors that Hunter Biden was "tired, exhausted, and looked like he hadn't slept" on the evening of Oct. 22 or early morning of Oct. 23, 2018, when he arrived at her home in Wilmington to sleep.

She observed that he "could've been" on drugs when she saw him -- just hours before she found his newly purchased Colt Cobra revolver in his car and discarded it in a dumpster.

"I went to clean out his car and his stuff" as he slept in her home, in hopes that when he awoke they could "start anew and deal with stuff," she testified, referring to his addiction to "both" drugs and alcohol.

The testimony didn't appear to be quite the smoking gun sought by prosecutors, who are trying to prove Hunter Biden was using crack at the time of his firearm purchase on Oct. 12 -- one of the central questions in the case.

Hallie Biden, who is the widow of Hunter Biden's late brother Beau Biden, testified that earlier in 2018 she also became addicted to crack after Hunter Biden introduced her to the drug -- but that she is now clean.

"It was a terrible experience I went through," she said, adding that she was "embarrassed and ashamed, and I regret that period of my life."