The founding fathers, whose brilliant design for the federal government was based on three coequal branches, would be horrified to learn of Attorney General John Ashcroft's latest idea for improving the American justice system. Mr. Ashcroft has ordered federal prosecutors to start collecting information on federal judges who give sentences that are lighter than those suggested by federal guidelines. Critics are right when they say this has the potential to create a "blacklist" of judges who could then be subjected to intimidation.

Congress established the United States Sentencing Commission in the mid-1980's, and charged it with developing guidelines to bring greater uniformity to sentences handed down by federal courts. The guidelines provide a range of sentences a judge can hand down for particular crimes. But they also permit judges discretion to impose a more lenient sentence, known as a "downward departure," if they can justify the decision. Judges frequently depart downward at the urging of the government, to reward defendants who cooperate with prosecutors.

But the administration and its allies in Congress have made no secret of their unhappiness with judges who impose more lenient sentences than guidelines call for. They have tried a variety of methods of pressuring judges to see things their way, including starting a Congressional investigation into the sentencing practices of James Rosenbaum, a United States District Court judge in Minnesota.

Mr. Ashcroft's latest initiative raises these pressures to a new level. Under the new policy, federal prosecutors will be required in many cases to report when a judge departs downward from the sentence recommended by the federal guidelines. The Justice Department has said it intends to use the data to identify how often particular judges depart downward. Obviously, judges are going to be worried about coming in high on the list, and those who do will wonder if they will be subject to intimidation, as Judge Rosenbaum was.

At the very least, the Ashcroft plan would subject federal prosecutors to an unusual, and undesirable, degree of top-down management. Right now, individual prosecutors decide when to appeal a judge's sentence. Mr. Ashcroft seems to want that decision to be made after a review from Washington. A prosecutor who feels a given judge is consistently handing down sentences that are too mild can certainly let his or her feelings be known to superiors. But this new, rigorous and rigid reporting system seems to treat prosecutors as lackeys, and judges as some kind of minor civil servants who can be ordered around by the president and his appointees.

By trying to make federal judges yield to political pressure from Washington, the Bush administration is engaging in a radical attack on our constitutional system. Even Chief Justice William Rehnquist, whose conservative credentials are unassailable, has warned that collecting data on judges' sentencing practices "could amount to an unwarranted and ill-considered effort to intimidate individual judges." Mr. Ashcroft should heed these words, and abandon his dangerous war on the judicial branch.