Let us hope that all the candidates for the White House, especially the two front-runners, read Bob Woodward's new book, "Shadow," some time this summer.

In the event that they are teachable, they will learn something important about the Oval Office, namely, that if you mess up you are going to be caught, and when you are, you would do best to come clean about your lapse--and spare yourself and your country a great deal of angst and embarrassment.

Woodward is the legendary legman, who with Carl Bernstein, brought down Richard Nixon. He has, according to sources--who later wish they hadn't been--a most seductive approach. He comes to the inner circle armed to the teeth with facts derived from archives and underlings and invites the target to give his or her own view for history. Knowing there will be no mortification in the morning paper and gratified to give a spin for the ages, many who should know better begin to sing.

Erstwhile White House press secretary Mike McCurry is rueful about his contributions, and former White House scandal manager Jane Sherburne, who sounds like a hard-nosed, high-elbows infighter, is loudly protesting that Woodward double-crossed her. He says he was able to confirm her "background" information from other sources. Lesser journalists, like me, envy Woodward his ability to get his foot in any door--repeatedly.

"Shadow" traces five presidents who, with the Watergate precedent staring them in the face, handled their own scandals in the same way. They lied, hedged and covered up, even though they knew in the case of Gerald Ford and Jimmy Carter that their hold on the electorate was a pledge not to do as Nixon did.

"Shadow" is a meticulously documented chronicle of self-delusion and self-pity. It is like an illuminated manuscript expanding on the old adage, "Honesty is the best policy." It is also riveting reading.

President Clinton studiously ignored Woodward's first law--when you are faced with ruinous scandal, tell all you can as soon as possible. Clinton is the only one of the five Nixon successors who actually, and inadvertently, wrote the lead for his obituary by being the second president in history to be impeached. The others, Ford, Carter, Ronald Reagan and George Bush, were not necessarily wiser, just luckier. Ford, out of an excess of good will toward old friend Nixon and party loyalty, pardoned him, in retrospect a sensible move. But he failed to see it could look like a deal and did not prepare the country. He paid the price.

Carter promised, "I will never lie to you." But when his old pal and OMB director, Bert Lance, offered to resign because of tangled accounts in his bank, Carter waved him away and tried to brazen it out. He paid for being self-righteous.

Reagan's story is another saga of a president who could have gotten away with almost anything, but spoiled his record in the Iran-contra imbroglio. Woodward paints a pathetic figure who was as stubborn as he was clueless and offered the country a limp alibi about a conflict between his head and his heart.

Bush's troubles came from the same source. He went along with the deal that Reagan insisted was not arms for hostages and claimed to be out of the loop. He was later lassoed by former defense secretary Caspar Weinberger's diaries, discovered late by minions of independent counsel Lawrence Walsh. Bush also paid: He was not reelected.

Almost half of the book is devoted to the scandal that still vibrates: Bill Clinton's insane affair with Monica Lewinsky. The material is familiar, but Woodward gives us some shocks about life in the Clinton White House that could lead to a national demand for fumigation.

It was calamity central, one disaster hard on the heels of another, a place of blunders, intrigue worthy of the Borgias, back-stabbings, a first lady alternately belligerent and distraught. You may gasp over the showdown over turf in which then-Deputy Chief of Staff Harold Ickes decants a stream of obscenities on Abner Mikva. Some people might think it was no way for one human being to talk to another, particularly a former federal judge. Then there's a toe-to-toe between the above-mentioned Sherburne and a sister scandal lawyer, Cheryl Mills, over what Bruce Lindsey said about the nature of James Riady's many visits to the Oval Office.

Presiding over it all was the president, who had two gears, whining and blowing up. He never blamed himself, and railed against Ken Starr, who comes off as pornographer. Maybe the hopefuls, who are about to be free of the independent counsel threat, will figure out that if they won't have a Starr they'll have the greater danger of a Woodward. One lapse should be noted. In the jacket picture of the five presidents, their wives have been erased. Woodward explains he wasn't consulted by the publishers. It's the only time that I can see that he was not in the loop.