US Vice President Mike Pence attends a news conference at the US Embassy in Ankara, Turkey. (Reuters)

Former US Vice President Mike Pence testified on Thursday in the federal inquiry looking into his ex-boss Donald Trump's involvement in the 2021 assault on the Capitol, as per media reports.

Pence testified before a grand jury in Washington that might decide whether to file charges against the former President and his advisors for their role in the attempt on January 6, 2021, to overturn the presidential election results that saw Joe Biden becoming President.

Pence's testimony had been challenged by Trump's legal team, who claimed that the President had the right to silence Pence due to executive privilege during his time in office.

On Wednesday a federal appeals court rebuffed Trump's appeal, and the former President appeared not to exercise his options of appealing the issue to the Supreme Court.

It is worth noting that Pence was the focal point of the January 6 riots because he was scheduled to preside over the US Congress as a whole to officially declare Biden as the winner of the November 2020 presidential election.

At the time, Trump had adamantly and repeatedly encouraged Pence to refuse to carry out the certification, using unsubstantiated allegations of widespread voter fraud and flimsy legal defenses.

He also reportedly incited thousands of followers to protest that day in Washington, a protest that turned into riots in the Capitol, forcing a halt to the certification.

A number of those directly engaged in the Capitol assault have been convicted of seditious conspiracy. Meanwhile, Trump is being investigated by Justice Department Special Counsel Jack Smith to look into whether the former President violated criminal laws.

This is happening as Pence considers challenging his ex-boss for the Republican presidential candidacy in 2024. Trump is presently the front-runner for the Republican nomination, and Democratic candidate Biden said on Tuesday he would run for reelection. This might lead to a déjà vu of the 2020 election.

Trump is under investigation for a number of probes, and on March 30, he was indicted on criminal charges — the first US President to undergo so — in a case involving giving an adult star hush money.

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