Attorneys for Hunter Biden have asked a judge to delay Biden's tax case set for June.
Biden wants the case delayed until September or later, according to The Hill.
The president's son stands accused of engaging in a tax conspiracy in the California case.
On Tuesday, Biden lost his latest attempt to delay the start of his Delaware criminal trial on gun charges, according to Politico.
Attorney Abbe Lowell, who's representing Biden, had told Judge Maryellen Noreika the defense team is not ready for the June start date because it has had difficulty finding expert witnesses who are willing to help the first son, especially regarding drug addiction and drug forensics issues.
Biden's attorney now is seeking a delay in the tax case to allow time between the two trials, The Hill said.
Biden's attorney said he will be in Delaware for the gun case until at least June 14. The tax case in California is due to start June 20. However, the pretrial dates overlap.