President Donald Trump really does have secret “tapes” of his telephone conversations with fired FBI Director James Comey, the Washington Post reported on Friday. And that may not be a good thing for Trump because he would be required turn over his recordings if subpoenaed by Congress or a special prosecutor.

The White House routinely makes digitized recordings of presidential phone calls and preserves text transcripts of the calls, the Post wrote.

That may be why Trump tweeted the word “tapes” in quotes — because the recordings are digital text transcripts, not audio recordings of actual voices.

Also Read: Trump Taping Comey Would Be Creepy - But Would It Be Criminal?

Trump did not start the practice of digitized recordings of presidential phone calls. The White House has been making digitized records of presidential phone calls since 2011, when Barack Obama was president, a former Homeland Security official told the Post.

White House Press Secretary Sean Spicer on Friday refused to say whether the White House has a secret audio taping system of the president’s phone calls or Oval Office meetings, or whether Trump secretly recorded his Jan. 27 one-on-one White House dinner with Comey when (according to media reports) the then-director of the FBI twice refused Trump’s demand that Comey pledge his loyalty to the president.

If Congress or a special prosecutor wants Trump’s digital transcripts of the president’s telephone calls with Comey — or if Trump secretly recorded his White House dinner with Comey — federal law requires Trump to preserve and surrender the recordings to investigators.

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Trump is required to preserve and archive any recordings made in the White House under the Presidential Records Act of 1978, a post-Watergate reform measure.

If Trump thinks he can claim presidential privacy under “executive privilege,” he’s mistaken. The Supreme Court decided unanimously in 1974 in the U.S. v. Nixon case that President Richard Nixon could not shield his White House audiotapes of conversations in the Oval Office from a subpoena.

Nixon resigned after his secret Oval Office tape recordings revealed that he had tried to obstruct a special prosecutor’s investigation of the break-in into Democratic Party offices orchestrated by the president’s aides.

The Post also suggested that Trump may have returned to Nixon’s practice of making secret audio tapes of presidential meetings with White House visitors.

Also Read: Democrats Demand Secret Trump Tapes - If They Exist

Trump has a history of recording his phone calls or having staff listen in when he was a businessman. He installed a “system for surreptitiously tape recording business meetings” in his Trump Tower office in Manhattan, according to an eyewitness account in Harry Hurt’s 1993 biography, “Lost Tycoon.”

After Trump tweeted on Friday morning about possible tapes of his conversations with Comey, two House Democrats sent a letter to White House counsel Donald F. McGahn, demanding that Trump turn over any such tapes.