On March 21, 1989, in Skinner v. Railway Labor Executives' Association and National Treasury Employees Union et al v. von Raab, the US Supreme Court went a long way in clarifying when a public or regulated employer can perform warrantless drug and alcohol testing in the absence of probable cause or reasonable suspicion. Much remains for the Court to resolve in delineating public interest over and against Fourth (unreasonable searches and seizures) and Fifth (due process) Amendment rights of public employees. However, it is clear that the Court will allow mandated drug and alcohol testing of all employees in dangerous jobs in governmentally regulated industries with a history of drug and alcohol related problems and of all employees in sensitive positions, or positions that require carrying firearms or performing jobs where drug interdiction is a primary function. The Court has approved the reliability of the tests used, and approved testing based on probable cause or reasonable suspicion for all government and nongovernment workers of regulated employers. Footnotes, bibliography