Among Federal and State courts that have considered such cases, a consensus has emerged. All courts which have ruled upon the validity of urine tests for public employees have required as a prerequisite some articulable basis for suspecting that the employee was using illegal drugs, usually framed as 'reasonable suspicion.' The decision as to whether a given search or seizure is reasonable requires a balancing of the need to search against the intrusiveness of a particular kind of search. Before invoking the protection of the fourth amendment, one must have a reasonable expectation of privacy. The U.S. Supreme Court has ruled that the expectation of privacy is reasonable if there is a subjective expectation of privacy and this expectation is recognized by society as reasonable. The court consensus indicates that President Reagan's Executive Order 12564 will have trouble withstanding a court challenge. This order requires that all Federal executive agencies collect and test urine from all Federal employees in 'sensitive' positions. 72 footnotes.