Attorney General Merrick Garland speaks at a press conference to announce arrests and disruptions of the fentanyl precursor chemical supply chain on June 23, 2023 in Washington. (PHOTO / AP)

WASHINGTON – The top Republican in the US House of Representatives is threatening an impeachment investigation of Attorney General Merrick Garland over the Justice Department's criminal probe of President Joe Biden's son, Hunter.

House Speaker Kevin McCarthy tweeted on Sunday that US Attorney David Weiss, the federal prosecutor appointed by Republican ex-president Donald Trump and overseeing the investigation, must answer questions about whistleblower allegations that the Justice Department intervened in the case to protect Biden's son

House Speaker Kevin McCarthy tweeted on Sunday that US Attorney David Weiss, the federal prosecutor appointed by Republican ex-president Donald Trump and overseeing the investigation, must answer questions about whistleblower allegations that the Justice Department intervened in the case to protect Biden's son.

"If the whistleblowers' allegations are true, this will be a significant part of a larger impeachment inquiry into Merrick Garland's weaponization of DOJ," McCarthy said, using the acronym for the Justice Department.

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Hunter Biden has agreed to plead guilty to two misdemeanor charges of willfully failing to pay income taxes and to enter as part of an agreement that could avert conviction on a gun-related charge, according to court documents filed last week.

Garland has denied Internal Revenue Service whistleblower testimony alleging that Weiss was hindered by the Justice Department from pursuing a more aggressive investigation of the president's son.

House Republicans, some eager to seek retribution for Trump who was impeached twice when Democrats controlled the House, have launched multiple investigations into Biden's family and administration to seek evidence of wrongdoing.

Trump, who faces multiple investigations and a federal indictment, is running for re-election in 2024.

Last week, two Trump allies introduced House resolutions to expunge the former president's 2019 impeachment for allegedly pressuring Ukraine's government to help him win re-election, and his 2021 impeachment over the deadly Jan 6 attack on the US Capitol by his supporters.

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McCarthy, who backs the effort to expunge Trump's record, has also leveled an impeachment threat against another Biden Cabinet member, Homeland Security Secretary Alejandro Mayorkas, over the administration's immigration policies.

Hardline Republican conservative Representative Lauren Boebert tried to force the House to vote to impeach Biden over immigration and border security last week.

Fellow hardline Representative Marjorie Taylor Greene is also pressing for the impeachments of Biden, Garland, Mayorkas, FBI Director Christopher Wray and a US attorney prosecuting participants in the Jan 6 attack on the Capitol.