How do you know when a White House press secretary is lying? Easy. His lips are moving.It's a cheap joke, and not entirely accurate. There have been White House PR people of great integrity, such as Jerry terHorst, who resigned from the Ford administration after his boss committed perhaps the clumsiest act of his Presidency and pardoned his predecessor Richard Nixon. But more recent members of this exclusive club have not exactly covered themselves in glory. Larry Speakes, who served in the Reagan White House, developed a new philosophy of PR, telling reporters, "If you say the same thing three times, it's true." And more recently, Democratic spokesmen echoed President Clinton's line that he had not had sexual relations with Monica Lewinsky, long after it became apparent to anyone who read the newspapers that he had. But those lies seem pretty harmless compared to the whoppers Ari Fleischer turned out on an almost daily basis. It's hard to imagine any press secretary in recent history has told more untruths per press conference than Fleischer, who announced this week that he's stepping down after three years selling President Bush's policies to the media and the American public. Fleischer began his tenure in the White House fueling the completely fabricated vandalism story; questioned about the President's movements on September 11, he claimed the White House had been a target of hijacked Flight 93, a claim that later proved false; he joined other members of the administration in massive deception during the planning and execution of the invasion of Iraq, on the supposed evidence of weapons of mass destruction, among other things; and most recently he attempted to defend President Bush's Michael Dukakis photo-op landing by jet on the deck of the USS Abraham Lincoln by claiming that the carrier was too far offshore to make the trip by helicopter. Said Timothy Noah, writing on Slate.com, "Ari Fleischer's ability to repeat a lie even after it's been shown, repeatedly, to be false is what separates him from the amateurs." Fleischer will undoubtedly land a cushy private-sector job, following in the footsteps of his predecessors. He certainly has his admirers. There's even an Ari fan site on the web, with messages from women who find his aggressive treatment of the White House press corps a big turn-on. But it's worth remembering that Fleischer was for three years the most high-profile public relations practitioner in the nation. Many members of the public formed their opinions about our craft by watching Fleischer at work. It's hard to imagine they formed an image of PR as a profession about openness, honesty, and integrity.