President Trump ordered his White House counsel and the attorney general on Wednesday to investigate former President Joseph R. Biden Jr. and his staff in Mr. Trump’s latest attempt to stoke outlandish conspiracy theories about his predecessor.
In an executive order, Mr. Trump put the power and resources of the federal government to work examining whether some of Mr. Biden’s presidential actions are legally invalid because his aides had enacted those policies without his knowledge.
The executive order came after Mr. Trump shared a social media post over the weekend that claimed Mr. Biden had been “executed in 2020” and replaced by a robotic clone, following a pattern of suggestions by the president and his allies that Mr. Biden was a mentally incapacitated puppet of his aides.
“The White House issued over 1,200 presidential documents, appointed 235 judges to the federal bench, and issued more pardons and commutations than any administration in United States history,” the executive order said, after asserting that “former President Biden’s aides abused the power” of his office.
A central claim of the conspiracy theory, as described by Mr. Trump himself, is that Mr. Biden’s use of the autopen system — which reproduces a person’s signature to be affixed to official documents — can legally invalidate those documents.
Mr. Trump has claimed, for example, that some pardons Mr. Biden had made during his time in office were invalid because they were signed using an autopen. (There is no power in the Constitution or case law to undo a pardon.)
Mr. Trump has acknowledged that his administration uses the autopen system on occasion. But his executive order asserts without evidence that the Biden administration’s own use of the system may have “implications for the legality and validity” of some of Mr. Biden’s actions as president.
The Justice Department’s Office of Legal Counsel had weighed in on this issue at the request of President George W. Bush in 2005.
Howard C. Nielson Jr., the top official at the Office of Legal Counsel, concluded that “the president need not personally perform the physical act of affixing his signature to a bill he approves and decides to sign in order for the bill to become law.” He added that the president instead could direct “a subordinate to affix the president’s signature to such a bill, for example by autopen.”
Mr. Nielson is now a Federal District Court judge in Utah, nominated to the position by Mr. Trump during his first term.