Trump can't legally force staff to sign NDAs -- yet

Robert Passman, the founding partner at Passman & Kaplan who specializes in federal employment law, said any new NDA for Executive Branch workers would have to be approved by the Office of Personnel Management.

“I don’t think OPM would allow it and I think it would be clearly improper,” Passman said.

He agreed with Cannon that the only thing Trump can really do to encourage political appointees’ silence is to take away their jobs. Trump’s go-to threat to sue somebody won’t be at his disposal as president.

“He can certainly tell them in advance that if they do talk he’ll fire them on the spot, and he can do that,” Passman said. “Otherwise you can’t sue a federal employee for any acts committed within the scope of their employment, except for very rare exceptions.”