An Affair to Remember.

An Affair of State: The Investigation, Impeachment, and Trial of President Clinton, by Richard A. Posner (Harvard, 276 pp., $24.95)

Unlike the unholy mess it dissects and untangles, An Affair of State is a cool little gemstone of logic and reason, a rational antidote to partisan excess, and a short, elegant guide for the perplexed. Among the first of what will be many books to look back at the Clinton-Lewinsky scandal, it should be the touchstone against which all others are measured, having no evident bias except toward clarity. Richard Posner, a federal appellate- court judge and lecturer at the University of Chicago law school, does not seem to like most of the people described in this book, much less to share their agendas. One cannot deduce here which party he backs, whom he voted for in recent elections, or whose positions he tends to endorse. This is the strength of his book, and its claim to authority.

Posner clarifies much that needed clarification. The precipitating event of the scandal was Clinton's alleged harassment of Paula Jones (a public matter), which resulted in the unearthing of his dalliance with Monica Lewinsky (a private affair), the attempt to conceal which (to avoid criminal sanctions) led to the crimes of perjury and obstruction of justice that brought on the impeachment and trial. The Jones case itself was a legitimate lawsuit that reached the heights it did largely because of partisan interests: Jones could not have paid for the kind of lawyers able to battle a president, had Clinton's conservative enemies not come forth to help. The Supreme Court was wrong to have let the case go on while Clinton was president, but Posner sees little wrong with the case as it developed. The Jones team was within its rights to contact Starr, as many criminal prosecutions begin with tips given by interested parties. And Starr had no choice but to pursue the issues raised in the Tripp matter, as the suspected crime there was obstruction of justice: Vernon Jordan was suspected of buying off people who could give Clinton trouble, offering them, for example, cushy jobs in New York.

The Jones suit was thus a valid legal case carried on largely for political reasons. The scandal involved a public lie about a private matter, to avert accountability in a legal (and public) proceeding, about a sin that was basically private in nature-not Clinton's lust for power, but his lust, period.

This set of facts gave rise to two quite different versions of events, which duked it out in a 14-month tangle. Each side inflicted significant damage but failed to land a knockout blow. The resulting confusion kept the public from forming strong feelings either way. It now seems likely that what was read as backing for Clinton was really indifference, or perhaps indecision. Yawns greeted the impeachment vote, the trial, and Clinton's acquittal. Yawns might have followed, had he been forced out.

Posner locates two smaller debates within the large dispute: The first was between "rigorists," who wanted Clinton removed so as to maintain the country's moral standards, and "pragmatists," who found Clinton disgusting, but not disgusting enough to justify a long, sordid trial. A second debate went on among activists, who fit the events into their private fixations. Social conservatives saw Clinton as the culminating figure in a long moral slide that had gone on since the '60s. "Progressives," thinking most conservatives fascists by nature, saw in the impeachment drive against a cultural liberal a second coming of the KKK. Also treated here, though perhaps not receiving as much attention as it deserves, is the extent to which this affair followed logically from the 1991 Thomas-Hill hearings, which made of sexual harassment a viable issue, made sex charges a weapon to use against "enemies," and bred in conservatives a justified lust for revenge.

On the trial itself, Posner keeps his cool, refusing to state the conclusions to which his assessments appear to be leading. "It is clear," he states, "that President Clinton obstructed justice, in violation of federal criminal law, by perjuring himself repeatedly in his deposition in the Jones case, in his testimony before the grand jury, and in his responses to the House Judiciary Committee"; by witness-tampering with Lewinsky, and perhaps with others; and by suborning perjury in Lewinsky's sworn deposition. These crimes, Posner says, would have been prosecuted more severely had Clinton been a private citizen, and the prison term for such offenses would probably be between 30 and 37 months.

But, he says, "the fact that obstructing justice is felonious is relevant but not determinative . . . neither so grave a crime as to make it imperative that the perpetrator be removed from office, nor so trivial" as to make removal excessive. (He also says that Richard Nixon might have been safely allowed to keep office, once his aides had been fired and the conspiracies exposed.) Correctly, he calls the Senate trial a "travesty," a truncated farce performed before jurors who had clearly made up their minds, and had no interest in listening to evidence. But he thinks the fault is less with this Senate than with the Senate as a modern institution: too large, too poll-driven, and too partisan to render fair judgment in all but the most obvious cases.

Posner lavishes dispraise on every side. He faults social conservatives as unduly gloomy, and insists that Clinton's sins neither presage nor reflect a general breakdown of morals. He's right to point out that private behavior among Americans did not become worse during the presidencies of Harding and Nixon; and that most indices reflecting social dysfunction- divorce, crime, abortion-rose in the administrations of moral men like Ford, Carter, and Reagan, and have turned around under Clinton.

But when he discusses liberals, his dispassion slips, and true feeling enters his arguments. He cites Clinton's lawyers as misleading and overly technical. He cites congressional Democrats as obstructionist demagogues who cheerfully argued conflicting positions and tacitly endorsed an alliance with the likes of Larry Flynt. He cites the White House's "slander machine"-Hillary Clinton, Sidney Blumenthal, and James Carville- for spreading malicious slurs about "enemies." And he cites Clinton's academic defenders-Sean Wilentz, Ronald Dworkin, and Arthur Schlesinger Jr.-for using the language of morals to mislead the public, to defend a liar and felon who happened to be of their party.

And what of Bill Clinton, the source of all this chaos? He is a shameless, endemic, and compulsive liar; along with Nixon, the most "abnormal" of our presidents; unfit morally (if not in strict legal terms) to hold his high office; incapable of shame, of conscience, or of "moral growth." When he was caught, Posner says, "it was apparent that . . . his reaction . . . was anger, not shame, that he would continue to blame everyone but himself . . . and that he would continue to lie to the extent that physical evidence would not contradict him."

Clinton is said to believe that history will vindicate him as the hero he thinks he is, hounded unfairly by Puritan zealots, jealous of his unparalleled greatness as president. Don't hold your breath, Bill.

Noemie Emery is writing a book on political dynasties.