Supreme Court Justice John Paul Stevens tonight delivered an unusual public critique of the high court's work, saying that its quality was being undermined by "unnecessary lawmaking" by the justices and an increasingly heavy caseload, which he called a matter of "national concern."

The caseload situation has become so severe, he said, that "anonymous" members of the court's administrative staff, rather than justices, are writing some unsigned opinions. In addition, he said that he personally never looks at 80 percent of the cases submitted to the court, but has his clerks review them.

Stevens suggested that the court should relinquish some of its power and allow a new court to be set up to choose which cases the Supreme Court will review.

Stevens' comments were prepared for delivery to the American Judicature Society, meeting here in conjunction with the annual convention of the American Bar Association.

The speech singled out a number of recent court actions for criticism, including a controversial ruling three terms ago against former CIA agent Frank Snepp.

Stevens said the Snepp case was an example of the court's "lack of judicial restraint" and "unnecessary lawmaking." He said the court did not need to go as far as it did when it allowed the government to impose a trust on the earnings from Snepp's book, "Decent Interval."

The Snepp case was decided by a per curiam opinion, unsigned by any justice and issued without a full hearing. Stevens attacked this practice and revealed that some of these rulings are "written for the court by an anonymous member of its ever-increasing administrative staff."

Stevens said the court is doing a poor job of screening cases submitted for review. As a result, he said, "We grant many more cases than we should, thereby making our management problem even more unmanageable."

In addition, he said, the court "often exhibits an unfortunate lack of judicial restraint" when it reviews novel issues prematurely, before lower courts to study them fully.