A state mental health department adopted a policy calling for the random drug testing of all of its employees. Three employees objected to the policy and sought a court order declaring it unconstitutional as applied to them. The employees held the positions of Psychiatric Assistant II and Office Support Assistants. The department claimed that the policy was justified because of its belief that illegal drugs were being used by some department personnel and because each employee serves as a caregiver and role model with respect to patients. The evidence regarding illegal drug use concerned employees at residential facilities for mentally retarded patients. The plaintiffs did not work at these facilities. Administrators were unable to cite specific individuals or incidents, but testified that they they had been informed by staff and family members that drug use by employees at these faciliities was occurring. The department also claimed that the need for its staff to act as role models applied to all positions, as well as to both in-patient and out-patient treatment. What should the court decide? Why?