John Dean, who went from Richard Nixon’s White House Counsel during the Watergate scandal to a caustic critic of the Republican party, is co-writing a book about the psychology of President Trump’s followers.

Indie press Melville House announced it would publish Authoritarian Nightmare: Trump and His Followers, written by Dean and psychology professor Bob Altemeyer, this summer. The book will “offer an eye-opening revelation of how Trump and his supporters have gotten where they are, and to consider where they may go next,” the publisher said in a news release.

“Donald Trump makes the problems that Richard Nixon created appear almost inconsequential,” Dean said in a statement. “I went to Bob Altemeyer to ask him to join me in writing this book because he has been studying authoritarian personalities for 40 years. I was eager to combine his more scientific expertise with my  first hand experience working for Nixon, our last authoritarian president.”

Dean was a central figure in the Watergate scandal, covering up evidence that a break-in at the Democratic Party headquarters had been organized by members of the Committee for the Re-election of the President. He pleaded guilty to obstruction of justice and served four months in prison.

Since then, he’s become a frequent critic of Republican politicians, particularly Trump, who, Dean has said, “should have been impeached the day he walked in.”

Authoritarian Nightmare is slated for publication on Aug. 25.

Michael Schaub is a Texas-based journalist and regular contributor to NPR.