Regular readers may recall that I have long considered John Dean to be one of the most despicable characters in American politics.

Not that I'm alone in my assessment. For years the man has been called a rat, and while "weasel" might be more accurate, such terms do a clear disservice to the animals involved. I'm sure he's been called a "snake" too, but snakes are only acting like snakes, just as weasels only act like weasels. I think "serial perjurer" is less anthropomorphic, and does not drag animals into logically unwarranted (and unfair) comparisons with humans.

Of course, because John Dean (who actually tried to claim the mantle of Barry Goldwater) spent years as one of the most vicious of Bush and Cheney bashers -- the whole while being portrayed as a "conservative" -- he is much loved by the left. No doubt, they can be expected to support him where it counts, and prop up his constantly unraveling version of Watergate.

The problem Dean faces is that Watergate history has never been settled. Historians remain puzzled over precisely who ordered the burglary, and why.

Dean, however, has devoted much of his life to suing people who have attempted to reexamine Watergate history. Like Len Colodny, Robert Gettlin, G. Gordon Liddy, St. Martin's Press, et al.

Recently (via Glenn Reynolds's link to a great post by Don Surber), I learned that Dean's latest move was to threaten to sue a history professor who posted and quoted Dean's own words. Why? Because the professor (Luke Nichter from Texas A&M) noticed what others have noticed -- Dean's disavowal of his own book on Watergate:

Dean, the former White House counsel whose damning testimony led to President Richard Nixon's resignation in 1974, is continuing what critics call a pattern of frivolous lawsuits meant to stifle questions about his role in Watergate. Now, a historian who runs a Web site dedicated to the Nixon tapes is feeling that pressure.

"I want to minimize my legal exposure," said Luke Nichter, the Texas A&M professor who runs Nixontapes.org, and who dropped two audio files from his Web site after receiving threats from Dean demanding that they be removed.

"It's an incident of a much broader pattern that this is how Dean treats people who present information contrary to his views."

Nichter had posted a 1989 phone call in which Dean disavowed the accuracy of his memoir, "Blind Ambition," the national bestseller that helped establish the public's view of the conspiracy to break into the Democratic National Committee headquarters in 1972.

Nichter set those admissions against a 4-minute tape from a June 2009 speech Dean gave at the Nixon Library promoting the re-release of his memoir. Dean's new edition did not change the content he has disavowed as the creation of zealous editors, though he added a 95-page afterword.

"I merely wanted to bring these contradictions to light and thought I was doing a service, but Dean was absolutely mortified when he found out that I had these materials," Nichter told FOXNews.com.

According to legal experts, the copyright claim flies in the face of the fair use doctrine, but of course, no one wants to be sued:

Dean argued that the recordings were made without his consent and violated his common law copyright, meaning that no one had the right to publish his speech and conversation in their entirety without his consent.

Legal experts contacted by FOXNews.com said that Nixontapes.org could not publish Dean's entire speech, but could run segments without Dean's approval, which is what Nichter was doing before he received the warning from Dean.

"To the extent that the Web site used the speech to comment on or criticize Dean, it may well have a strong fair-use argument," said Kurt Opsahl, a senior staff attorney with the Electric Frontier Foundation. That would allow Nixontapes.org to provide a portion of the audio without Dean's authorization.

And common law copyright wouldn't cover the informal conversation in the 1989 phone call, said Professor Tyler S. Ochoa of the High Tech Law Institute at Santa Clara University School of Law. Even if it were applied in court, "it is outweighed by the interest in free speech," he said.

That's why we have the First Amendment.

And, by suing and attempting to intimidate historians and authors with his legal threats, Dean is demonstrating his contempt for history as well as the First Amendment:

Several authors and journalists who spoke to FOXNews.com said Dean uses the threat of litigation as a bullying tactic to silence his critics. Some would not speak for fear of being sued by Dean, including Jim Hougan, who wrote the first revisionist history of Watergate, 1984's "Secret Agenda."

"I can't talk about this because I am afraid John Dean will sue me," Hougan wrote in an e-mail to FOXNews.com. Hougan was one of many targets in a lawsuit instigated by Dean in 1992.

"He's very quick to react and threaten legal action and most of the time people back down," Nichter said.

Dean has also threatened FOX News correspondent James Rosen with a lawsuit over his 2008 biography of former Attorney General John Mitchell, "The Strong Man," which pointed to Dean as the leading figure in the planning of Watergate.

While Wiki entries on the subject of Dean's disavowals and discrepancies are notorious for being whitewashed, I was surprised to find that as of today, the entry for Dean's ghostwriter (the distinguished, Pulitzer Prize-winning author Taylor Branch) says this:

In October 1976, Simon & Schuster published Blind Ambition, which purports to be, mainly, a Watergate-related memoir by John Dean, the former White House Counsel to President Richard Nixon. On several occasions, Taylor Branch has publicly stated that he was the ghostwriter for this book. John Dean has denied this, and in 1995 gave sworn deposition-testimony that Taylor Branch actually wrote large sections of the book without his (Mr. Dean's) participation, knowledge, or approval. John Dean claimed furthermore that these sections written by Taylor Branch were partially fictional. Taylor Branch has, in turn, denied John Dean's claims, and continues to assert, including on his website (cited below under "External links"), that he was, in fact, the ghostwriter for "Blind Ambition," and that all of the book's content originated with Dean.

Last year, Rosen wrote a biography of former Attorney General John Mitchell. In the course of his years of research, it became clear to him that the conventional version of the burglary whodunit (Dean says Mitchell ordered it) was wrong, and that it was Dean himself who ordered the burglary for personal reasons. Obviously, this poses problems for Dean, because his testimony sent John Mitchell to prison, and if that testimony was false, then Dean becomes more than just a liar, and more than just a rat. Little wonder he's threatening to sue.

Here's an interview with Rosen:

Whether or not John Dean was lying, and whether or not his false testimony sent John Mitchell to prison, the fact is that John Mitchell is as dead as Richard Nixon, so these things are not considered to be of earthshaking relevance to most people today. They're of interest mainly to historians and political junkies.

But the idea that certain unsettled historical facts should be off limits to historians because John Dean says so, that ought to offend everyone.

I'd even go so far as to say that a weasel or a snake would be offended, but that would be too anthropomorphic.