Hunter Biden is facing nine new tax charges made against him as the investigation into him continues.
The new charges include three felonies and six misdemeanours.
They will be added to a series of federal firearms charges, in which the state of Delaware alleges Hunter Biden broke several laws against drug users having guns in 2018.
The fresh charges came out on Thursday, shortly after the implosion of a plea deal that would have spared him jail time - and right in time to potentially throw a spanner in the works of his father's campaign for re-election.
Special counsel David Weiss described Mr Biden, aged 53, as a man who "spent millions of dollars on an extravagant lifestyle rather than paying his tax bills".
The charges are centred on at least $1.4million(£1.2million) in taxes Mr Biden owed between 2016 and 2019, a period where he has acknowledged struggling with addiction.
The back taxes have since been paid.
In a fiery response, defence attorney Abbe Lowell accused Mr Weiss of "bowing to Republican pressure" in the case.
"Based on the facts and the law, if Hunter's last name was anything other than Biden, the charges in Delaware, and now California, would not have been brought," Mr Lowell said.
The White House declined to comment on Thursday's indictment, referring questions to the Justice Department or Hunter Biden's personal representatives.
If convicted, Mr Biden could face a maximum of 17 years in prison. The special counsel probe remains open, Mr Weiss said.
