When the creators and backers of the judicially stricken "special prosecutor" law raise their misplaced laments, one very significant name is usually missing: Leon Jaworski.

The late Mr. Jaworski, a distinguished Texas lawyer and former American Bar Association president, followed Archibald Cox as Watergate special prosecutor, after the "Saturday night massacre."

Jaworski, to the surprise of many skeptics who mistook him for a Nixon administration stooge, pressed the investigation to a successful conclusion, forcing the surrender of Richard Nixon's incriminating White House tapes and sending several top Nixon aides to jail in the Watergate cover-up.

Presumably, Jaworski goes unmentioned because his performance refutes the principal claim of the new law: that special prosecutors cannot be effective unless they are wholly independent of the administrations they probe.

This assumption led Congress to enact an unsound and unconstitutional device -- transferring the appointment and control of special prosecutors from the White House and Justice Department to the federal courts.

As Jaworski's performance and others before it prove, however, there were effective special prosecutors before there was ever an Ethics in Government Act. True, they were all presidential appointees, theoretically or actually removable in some instances by the very people whose misbehavior they were supposed to investigate. But they succeeded because the backing of Congress and the power of public opinion made it impossible for administrations to tamper with or hinder them.

Indeed, as Judge Laurence Silberman notes in his masterly opinion, when President Truman's attorney general improperly dismissed a special prosecutor of the late 1940s who was probing the so-called Truman scandals, Truman fired the attorney general and promptly hired another special prosecutor. And he did this in spite of the potential political embarrassment to his own presidency.

It is no doubt true that without the 1978 act, Washington would not be teeming, as it is today, with special prosecutors. But that is far from saying that special prosecutors would not be appointed when occasion warranted. Congressional investigations have again and again forced conspicuously corrupt administrations to clean house -- and, when necessary, to do so by appointing independent special prosecutors and giving them the necessary political insulation to do their jobs effectively.

The law the court of appeals has now overturned, by a 2-to-1 decision, raises altogether new but vitally important constitutional issues.

In its stampede to guard against future Watergates, Congress overrode the central principle of liberty, the separation of powers.

By authorizing the appointment of special prosecutors (or independent counsels, as the law now calls them) by courts, it concentrated every vital step in the house-cleaning process in one branch of government. Under the special counsel section of the 1978 Ethics in Government Act, judges not only appoint special prosecutors. They define the scope of their duties, supervise them and may even remove them or terminate their investigations.

But if these court-appointed prosecutors bring an indictment, judges preside at the trial and then, if the verdict is guilty, hand out sentences. And colleagues on the very same federal court may even, in the end, review the ultimate consequences.

This is a gross violation of the separation-of-powers principle, the intricate system of checks and balances we rely upon to prevent concentration of power at the expense of individual liberty.

Article II of the Constitution plainly requires that all who perform significant executive duties (as prosecutors do) be appointed by the president and accountable to him, as he is answerable to the voters at the next election.

In fact, there is only one argument in favor of court-appointed special prosecutors: the argument from necessity. And it is a very treacherous argument indeed.

As Judge Silberman writes: "Congressional desire for more effective administration of the criminal law when high government officials are implicated cannot justify departure from a constitutional plan carefully calibrated to balance the need for law enforcement against concerns for individual liberty."

On that everlastingly sound principle, Judge Silberman has built an unanswerable case.