President Joe Biden's son, Hunter Biden, has sued the US Internal Revenue Service, alleging unlawful disclosure of his taxes by whistleblowers who work for the US tax agency.
The lawsuit focused on statements made by IRS agents in media interviews amid a long-running investigation by House of Representatives Republicans into the younger Biden's taxes and business dealings.
Hunter Biden is at the centre of a political vortex, as House Republicans mount an impeachment inquiry against his father focused on alleged ties between his business practices and his father's policies during the older Biden's tenure as vice president from 2009 to 2017.
No evidence showing that the elder Biden profited from his son's businesses have been presented so far. The White House has also denied any wrongdoing.
Hunter Biden is the first child of a sitting US president to have been criminally indicted. Prosecutors last week charged him with three counts related to the fact that he was lying about using illegal drugs when he bought a firearm.