As you know,” President Clinton told the American people Monday night, ”in a deposition in January, I was asked questions about my relationship with Monica Lewinsky. While my answers were legally accurate, I did not volunteer information.” With those words, Clinton guaranteed that at least part of his historical reputation will be as an incorrigible liar.

Did he also lie to the grand jury that day, cementing the case for impeachment? Or did he manage to avoid that, by spurning, as ”too private,” all of the questions that he would have had to answer falsely to avoid helping Starr prove that he had lied in his Jan. 17 deposition? That’s one of the questions Congress will soon ponder.

Two other questions are ponderable today: Did the president in fact lie in that Jan. 17 deposition? Did he commit the felony of perjury? No, he said Monday night, he certainly did not: ”My answers were legally accurate.” But this was another, defining, lie. And this time, Clinton was lying not about sex, but about lying itself; he was lying to protect, not anyone’s privacy, but his own image.

”Legally accurate”? Consider some excerpts from the Jan. 17 deposition, as Clinton bobbed and weaved and misled and– yes–lied his way through dozens of questions aimed at uncovering whether he had engaged in sex with Lewinsky and had encouraged her to conceal evidence that the judge in the Paula Jones lawsuit had held to be relevant:

Q: At any time, were you and Monica Lewinsky together alone in the Oval Office?

A: I don’t recall, but as I said, when she worked at the legislative affairs office, . . . it seems to me she brought things to me once or twice on the weekends. In that case, whatever time she would be in there, drop it off, exchange a few words and go, she was there. . . .

Q: So I understand, your testimony is that it was possible, then, that you were alone with her, but you have no specific recollection of that ever happening.

A: Yes, that’s correct. . . .

Q: At any time, have you and Monica Lewinsky ever been alone together in any room in the White House?

A: . . . . I have no specific recollection, . . . .

Q: Did she tell you she had been served with a subpoena in this case?

A: No. . . .

Q: Well, have you ever given any gifts to Monica Lewinsky?

A: I don’t recall. Do you know what they were? . . .

Q: Did you have an extramari tal sexual affair with Monica Lewinsky?

A: No.

Q: If she told someone that she had a sexual affair with you beginning in November of 1995, would that be a lie?

A: It’s certainly not the truth. It would not be the truth.

Q: I think I used the term sexual affair. And, so the record is completely clear: Have you ever had sexual relations with Monica Lewinsky, as that term is defined in Deposition Exhibit 1, as modified by the court? . . .

(The modified definition states: ”For the purposes of this deposition, a person engages in ‘sexual relations’ when the person knowingly engages in or causes . . . contact with the genitalia, anus, groin, breast, inner thigh, or buttocks of any person with an intent to arouse or gratify the sexual desire of any person.”)

A: I have never had sexual relations with Monica Lewinsky. I’ve never had an affair with her.

This is the progression of lies that the president claims was ”legally accurate.”

The main rationale floated by the president’s hairsplitters for that claim is that, while Lewinsky had ”sexual relations” with Clinton, he had no ”sexual relations” with her. Only in America, land of a million lawyers, could so preposterous a proposition be presented with a straight face.

This one-way-sex, look-Ma-no-hands defense requires both a tortured reading of the definition and a factual premise both ludicrous on its face and explicitly contradicted by Lewinsky’s reported account of reciprocal sexual contacts: the premise that while being sexually serviced by her for many months, Clinton never once reciprocated, never once touched her intimately.

If Starr’s prosecutors did ask intrusive questions on Monday about the Clinton-Lewinsky sexual encounters–as suggested by leaks from the Clinton camp–Clinton left them little choice. Had he been willing to admit that his Jan. 17 answers were false, no exploration of the salacious details would have been necessary.

In any event, even indulging the improbable notion that Clinton was ”legally accurate” when he denied having ”sexual relations” with Lewinsky, that would support only the first sentence of the final answer quoted above. It has no bearing on Clinton’s lies in denying a ”sexual affair” with her; in denying any ”specific recollection” of ever having been alone with her; in asserting that if they ever were alone it was only briefly, on routine, official business; and more.

Those lies clearly fit even a narrow reading of the Supreme Court’s definition of perjury as a literally false, unambiguous statement made with intent to deceive. And contrary to a myth recently popularized by the Clinton camp, perjury convictions–including that of Watergate defendant Dwight Chapin, for example–can be based on ”I-don’t-recall” answers when, as here, the circumstances make the claimed lapse of recollection utterly incredible.

To be sure, the perjury statute also requires that the defendant’s lie be ”material,” a term defined by courts to include testimony having ”a natural tendency” to affect a judge’s or jury’s decision, even slightly, at the time the testimony was given. It can be argued that even though Clinton lied repeatedly on Jan. 17, he did not commit perjury, because the Lewinsky evidence was not ”material” to the Paula Jones lawsuit.

This argument rests on the subsequent decisions (now being appealed) of Judge Susan Webber Wright to exclude the Monica Lewinsky evidence and, later, to dismiss the entire Jones lawsuit. Contrary to some news reports, Judge Wright did not hold the Lewinsky evidence to be immaterial; rather, she ruled that it ”might be relevant” but was ”not essential to the core issues in the case.”

While reasonable lawyers disagree about whether Clinton’s materiality argument is plausible or weak, some precedents hold that lying under oath in a civil deposition can be material even if the testimony is later excluded or the case is dismissed.

And even if Clinton’s Jan. 17 lies were not material, and thus not perjury, they may still have been criminal violations of the obstruction of justice statute–especially if Starr can prove them to be part of a broader pattern of efforts by Clinton to hide evidence or encourage others to do so.

More to the point here, Clinton did not content himself on Monday with contending that his Jan. 17 lies may not have been material enough to amount to perjury as a matter of law. He claimed that he had not lied at all. Thus did he lie yet again.

Clinton’s coverup of his sexual activities is not in a league with Watergate. But there are some parallels. One is suggested by the first article of impeachment against President Nixon, charging him with obstruction of justice. In addition to Nixon’s ”false or misleading statements” to investigators, and his withholding of evidence, and his encouragement of similar actions by others, that article cited Nixon for making ”false or misleading public statements for the purpose of deceiving the people of the United States.”

Clinton’s persistence in lying to the nation, as well as under oath, therefore strengthens the case for impeachment.

We should nonetheless dread the prospects of an actual House vote to impeach and of a Senate trial. That would paralyze our polity, embolden foreign enemies, and bring many years of bitter, partisan recriminations no matter what the outcome. The closer we get to the natural end of Clinton’s term, the more the costs of such a battle would outweigh the benefits.

That doesn’t mean we should just call the whole business off and turn to ”healing.” The law, and the truth, have their claims. Starr has a statutory mandate to send to the House any evidence that ”may (emphasis added) constitute grounds for an impeachment.” The law appears to oblige him to do that, regardless of whether Starr himself would (were he a Congressman) vote to impeach. It will then fall to the House to expose and explore, in public hearings, the evidence for and against the president.

As Starr’s evidence cuts through the fog of lies and spin, Democratic leaders will have to decide whether to palliate the president’s lies or to denounce them. They must also consider whether, at long last, to give him some advice: For God’s sake, go.