The documents could have been signed by a robot without the former president's knowledge, the current US leader has alleged

US President Donald Trump has claimed that pardons signed by his predecessor, Joe Biden, lack legal force, alleging they were never properly considered and authorized.

Shortly before leaving office, Biden granted preemptive clemency to several political figures, including members of the Congressional select committee for the Capitol Hill riot of January 6, 2021, who his administration argued might face unwarranted prosecution under the second Trump presidency.

In a post on Truth Social on Monday, Trump dismissed the pardons as "VOID, VACANT, AND OF NO FURTHER FORCE OR EFFECT," claiming that "Biden did not sign them but, more importantly, he was completely unaware of them!"

The legitimacy of the pardons has come under scrutiny this month after the Oversight Project, an initiative within the conservative Heritage Foundation, highlighted the extensive use of an autopen device for signing official documents during Biden's tenure. The report claimed, "Whoever controlled the autopen controlled the presidency."

While there is no legal requirement for a US president to sign documents by hand, suspicions have arisen due to Biden's frailty in the latter years of his presidency that staff may have exploited the situation to secretly misappropriate presidential powers.

Trump alleged that members of the January 6 committee orchestrated their own pardons without Biden's knowledge or consent. "The necessary Pardoning Documents were not explained to, or approved by, Biden. He knew nothing about them, and the people that did may have committed a crime," Trump stated.

The president expressed similar sentiments during a speech at the Department of Justice last Friday, labeling Biden's use of the autopen as "disrespectful to the office" and potentially "not even valid."

READ MORE: Biden's pardons should be investigated - Missouri AG

US leaders have utilized writing assistance tools for over two centuries. In the early 1800s, Thomas Jefferson brought a duplication device known as the polygraph into the White House to copy his handwritten letters. The administration of George W. Bush made the legal argument that the autopen serves as a legitimate substitute for a president's signature on bills.