EXCLUSIVE: The White House is investigating former President Joe Biden’s use of the autopen, with senior administration officials telling Fox News Digital that they already are reviewing tens of thousands of documents turned over by the National Archives and Records Administration.

On Biden’s final day as president, January 19, he met with his advisors until almost 10 p.m. to discuss different preemptive pardons, according to the Times. According to emails acquired by the Times, at 10:03 p.m., an aide gave Zient’s assistant a summary draft of the official decisions made at the meeting.

Trump said that the autopen use is "one of the biggest scandals" in "50 to 100 years" because Biden "knew nothing about what he was signing."

When the president is traveling, time-sensitive documents – such as bills to keep the government open – may need a signature right away, and it’s not always feasible to fly the original documents to wherever the president is.

Facing questions about his mental acuity, the former president told The New York Times he made all clemency decisions.