Hunter Biden pleaded not guilty on Thursday to nine tax-related charges in a federal court in California, multiple outlets reported.

The big picture: It's the second set of charges President Biden's son has been arraigned on in recent months. In addition to federal tax and gun charges, he is also facing the prospect of contempt of Congress charges for defying a subpoena issued by House Republicans.

• The hearing lasted about 30 minutes, per NBC News. Biden also reportedly confirmed to Judge Mark C. Scarsi he understood his risk of arrest.

Catch up quick: The Department of Justice in December filed the tax charges against Hunter Biden, including evasion of assessment, failure to file and pay taxes and false or fraudulent tax returns.

• The indictment alleges that the president's son "spent millions of dollars on an extravagant lifestyle rather than paying his tax bills."
• Hunter Biden's attorney has said the charges were brought against him because of his connection to the president, years after Hunter Biden paid his taxes in full.

State of play: Hunter Biden pleaded not guilty in October to federal gun charges. He is accused of falsifying a federal firearms form and illegal possession of a firearm while using a narcotic.

• His attorney asked a judge to dismiss the charges in December, saying they were "unconstitutional under the Second Amendment."
• GOP-led House committees have sought to link President Biden to his son's financial dealings and legal troubles in an impeachment inquiry that the White House has said is baseless.

Editor's note: This story has been updated with additional details.

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