Partisans in the quarrel of Bush vs. Congress have the satisfaction of knowing that weighty arguments can be made in behalf of either position. Presidential immunity respecting the operations of members of the executive branch can be upheld as vital to the balance of powers. Meanwhile, others can persuasively maintain that the doctrine of executive privilege has been abused in the past and is probably being abused at this moment by President Bush.

Every now and then there is a judicial finding in these controversies. But more often than not, both sides tend to give a little and compromises are reached. While granting the theoretical force of the contending positions, the viewing public should be prepared to look at a few other considerations.

It is obvious that there are Democrats in Congress who want an opportunity to forage for crimes in the matter of the discharged U.S. attorneys. Nobody has come up with a description of exactly what crime might have been committed and should be investigated. What is being conjectured is that an industrious investigating committee armed with subpoena powers could come up with malfeasance of some kind.

On the other hand, the investigative function of the legislative branch is of plenary importance, and should not be aborted by hypothetical immunities of the chief executive. Woodrow Wilson wrote in his classic book "Congressional Government" that Congress' investigative power was more important, even, than its legislative power.

The terrain of executive privilege is littered with difficulties. Imagine, for example a tobacco company that is sued by cancer-stricken smokers. The company wants to defend against the lawsuit by claiming that federal subsidies to tobacco growers show that national policy permits (and even supports) smoking. Toward this end, the company wants to take testimony from the secretary of agriculture about his conversations with the president regarding subsidized farming. Does immunity apply?

At present, the investigators want to focus on the question whether one or more U.S. attorneys were discharged simply because they were doing their duty, and that duty included refusing to speed up the prosecution of various Democrats. But in the matter of any one of the fired attorneys, guilt might be found to attach to the attorney himself -- he abused his authority by protecting a friend, or by persecuting an enemy -- or to the attorney's superiors, reaching right up to the White House.

Bear in mind that several committees of Congress can legitimately be interested in particular deficiencies involving the attorneys under consideration. But in the absence of persuasive evidence that these deficiencies involved the commission of crimes, the president's claim to executive privilege will be hard to gainsay.

There is one area of investigation concerning which a president clearly cannot shield himself from exploration. That is the charge of malfeasance of office justifying impeachment. In the case of U.S. v. Nixon in 1974, Nixon attempted to withhold the famous tapes, pleading executive privilege. But he was quarreling with a special prosecutor who was in search of evidence on the matter of Watergate. The Supreme Court ruled that the president could not preserve from scrutiny data which would reveal whether federal crimes had been committed. As indeed they had been, which brought about the resignation from office of Mr. Nixon and would certainly, had he failed to resign, have brought on his impeachment.

Of one thing Mr. Bush is manifestly guilty. It is the criminal (in the metaphorical sense) mismanagement of the whole business of the U.S. attorneys. The fault is not personal; it was probably the attorney general and other advisers of the president who took so many clumsy steps. But Mr. Bush's stress on his rights invites a coordinate stress on his responsibilities. "These attorneys," he said, "serve at my pleasure." Right. But presidential pleasures have to rest on defensible grounds.