Earlier on Sunday, Biden accused Republicans of unfair treatment and claimed Hunter was "treated differently" by prosecutors. Hunter Biden was convicted of three felony firearm offenses in a Delaware trial earlier this year, and then pleaded guilty to multiple felony tax offenses in September.

In a joint statement, IRS special agents Gary Shapley and Joe Ziegler blasted Joe Biden's explanations for the pardon of his son as "excuses."

Hunter Biden has responded to his pardon in a new court filing. He informed a federal court that his father, President Joe Biden, had pardoned him of federal tax evasion and gun crimes. "Joseph R Biden Jr granted me a full and unconditional pardon for, inter alia, the offenses specified in the indictment in this case," he wrote.