WASHINGTON - A judge on Monday denied a bid by US President Joe Biden's son, Hunter, to dismiss a federal tax evasion case brought against him in California.

Hunter Biden was convicted in Delaware in June for lying about his illegal drug use to buy a gun, and is scheduled to go to trial in September in the tax evasion case.

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Biden, who has pleaded not guilty to the tax charges, had argued that David Weiss, the special counsel leading both prosecutions, was illegally appointed.

The president's son had relied on a federal judge's decision dismissing a criminal case accusing former President Donald Trump of illegally retaining classified documents after leaving office.

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Florida-based US District Judge Aileen Cannon found the appointment of the special counsel in that case, Jack Smith, violated the US Constitution because Congress had not given him the authority to pursue the case. Smith's office is appealing.

But US District Judge Mark Scarsi in Los Angeles said on Monday there was no valid basis to reconsider a prior order denying Hunter Biden's bid to throw out the tax evasion indictment.

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"The court declines to reach the merits of the motion because there is no valid basis for reconsideration of the court’s order denying Mr Biden's motion to dismiss," the judge wrote.