GOVERNMENT employees who oppose being subjected to random drug tests have suffered a series of unexpected setbacks in court. After a string of victories in state and federal district courts, U.S. courts of appeal in three different circuits have reversed judgments, and the Supreme Court has twice in eight days refused to give these rulings special treatment. None of this looks good for the prospects of a broad suit challenging the president's executive order that authorizes testing of as many as 2.2 million civilian federal employees.

In three recent cases appellate courts have upheld random drug tests of prison guards, city transit workers and race-horse jockeys. In another case, a union representing U.S. Customs Service agents had brought suit in New Orleans challenging rules requiring mandatory urinalysis for all people seeking jobs or promotions in certain areas of the service. Last November, a trial court declared that the tests violated the Fourth Amendment prohibition against unreasonable search and seizure, but in April the ruling was overturned on appeal. Last week the Supreme Court refused to grant the union's request for a stay, and on Monday the same court refused to give expedited treatment to the appeal. This case is particularly troubling for federal employees because it has been heard in the judicial circuit where a much more comprehensive drug-testing suit has been filed, one that tests the president's executive order mandating random tests of all federal employees in security "sensitive" positions. It is estimated that half the government's civilian work force would be covered.

Drug tests are a fact of life in some areas of private employment. They are routinely given where public safety is a factor -- to airline pilots, for example -- and some businesses even impose them where employee efficiency is the objective. But the courts have always applied a more rigorous, Fourth Amendment, standard when government is the employer. If drug tests are a search -- and not just a fitness test for employees -- then they must be reasonable.

In the case of Customs agents, the appellate court found that it was reasonable for the government to screen for drug use those employees whose jobs involve drug interdiction, access to classified information or the carrying of a gun. Whether the testing of millions more simply because they serve in sensitive positions will meet the same standard is still at issue. If the courts continue to authorize indiscriminate testing, Congress should act to curb i