Former President Donald Trump insisted on Tuesday that he was not showing off classified documents in an audio clip first published by CNN in which he referred to “highly confidential” material and “secret information” that he could no longer declassify.

“I would say it was bravado, if you want to know the truth, it was bravado,” Trump said in an interview aboard his plane with Semafor and ABC News. “I was talking and just holding up papers and talking about them, but I had no documents. I didn’t have any documents.”

According to former U.S. Attorney Joyce Vance, that’s a flawed defense, especially if Trump tries it in court.

“If your best defense is ‘bravado,’ in essence you’re saying ‘my defense is that I was lying,’” Vance told MSNBC. “That’s a terrible defense, certainly for a former president and for anyone to make in front of a jury.”

Further, she said, Trump would probably have to take the witness stand to present this story.

“And that’s just something he can’t do,” she said. “No lawyer could let Donald Trump take the witness stand in his own defense without committing malpractice.”

Trump’s legal team potentially could put together some of his media appearances to show the jury as a workaround, Vance added.

“But at the end of the day, you still have a defendant telling the jury: ‘Hey, I’m a liar, so you shouldn’t convict me,’” she said.