We could take him at his word
"Hunter Biden has revealed that at the height of his addiction he found himself picking through rugs, looking for and smoking 'anything that even remotely resembled crack cocaine.'" Link
His word is legally useless. What did he affirm on the form to buy the gun? If he affirmed he wasn’t using drugs at the time, and nobody did a chain of custody solid drug test to prove he lied, all the freelance storytelling counts for nothing in a court of law. So he made up drug stories? So did Hunter Thompson, the gun nut.