Story highlights Trump tweeted, 'James Comey better hope that there are no 'tapes' of our conversations before he starts leaking to the press!'

Former FBI Director James Comey said in his testimony, 'Lordy, I hope there are tapes'

Washington (CNN) For President Richard Nixon, the controversy over his secret White House tape recordings began with a break-in at the Watergate Hotel. If President Donald Trump is also keeping recordings of his conversations, any controversy over those will have begun with a tweet.

On May 12, three days after firing FBI Director James Comey, Trump tweeted: "James Comey better hope that there are no 'tapes' of our conversations before he starts leaking to the press!"

Since then, the possible existence of audio recordings of Oval Office conversations have been a topic of conversation among many on Capitol Hill. The House intelligence committee has called on both the White House and Comey to hand over any material related to its Russia investigation, including memos and recordings, by June 23.

But two questions remain: Are there actually audio recordings? And, if so, do Trump and the White House have to hand them over?

"The short version is, if there are tapes, and if they are subpoenaed, I think the White House will probably have to turn them over," said Stephen Vladeck, a professor at the University of Texas School of Law and a CNN legal analyst.

Read More