Q: It looks pretty clear that former President Barack Obama did not order wiretaps on then-candidate Donald Trump, but Trump is not backing down on his tweets, issued after he was inaugurated. Can Obama sue Trump for libel? If so, would Trump have to be out of office first?

—Bruce Burnaman, Woodstock

A: It is unlikely in the extreme that Obama would bring such an action, Geoffrey R. Stone, the Edward H. Levi Distinguished Service Professor of Law at the University of Chicago, told Q&A on the News via email.

“However, were the impossible to happen, he clearly would win a libel action against Trump on the merits,” he wrote. “There is no doubt that Trump’s assertion that Obama committed a criminal action was false, libelous and made with reckless disregard for the truth.”

The question is whether Trump would have immunity from such a suit. In the 1997 Clinton v. Jones lawsuit brought by Paula Jones against former President Bill Clinton, the Supreme Court unanimously held that a sitting president has no immunity from civil law litigation against him for acts done before taking office and unrelated to the office, Stone wrote.

In the hypothetical case of Obama versus Trump, he wrote, the courts would have to determine whether the tweet in question was an exercise of Trump’s official duties as president of the United States.

“If so, that would give him immunity from suit,” he wrote.

Fast Copy News Service wrote this column. Do you have a question? We’ll try to get the answer. Call 404-222-2002 or email q&a@ajc.com (include name, phone and city).