480 U.S. 709 (1987), Supreme Court of the United States
O'Connor v. Ortega is a foundational Fourth Amendment case defining the constitutional limits on workplace searches by government employers.
Does the Fourth Amendment require a warrant and probable cause for a public employer to search an employee's office, desk, or files, or are such searches for noninvestigatory, work-related purposes or for investigations of work-related misconduct judged by a general reasonableness standard?
A public employee may have a reasonable expectation of privacy in the workplace based on the operational realities of the office (e.g., policies, practices, shared access, and customary use). When a public employer conducts a search for noninvestigatory, work-related purposes or to investigate work-related misconduct, the search is subject to the Fourth Amendment but need not be supported by a warrant or probable cause. Instead, it is assessed under the general reasonableness standard of New Jersey v. T.L.O.: (1) it must be justified at its inception (i.e., there are reasonable grounds to believe the search will yield evidence of work-related misconduct or is necessary for a work-related purpose), and (2) it must be reasonably related in scope to the objectives of the search and not excessively intrusive in light of the circumstances and the employee's privacy expectations. Traditional warrant and probable cause requirements continue to apply where the government acts as law enforcer rather than as employer.
The Fourth Amendment applies to searches of a public employee's office, desk, and files by a government employer. For noninvestigatory, work-related searches and for investigations of work-related misconduct, the proper standard is reasonableness under all the circumstances, not a warrant or probable cause. The Court vacated and remanded for application of this standard to determine Ortega's reasonable expectation of privacy and the reasonableness of the search.
O'Connor v. Ortega is the leading case on public workplace searches under the Fourth Amendment. It clarifies that the government's dual role—as sovereign and as employer—matters: when acting as employer to manage its offices or to investigate work-related misconduct, the government may conduct warrantless searches that are reasonable at inception and in scope. The decision instructs courts and agencies to evaluate employee privacy expectations based on actual workplace practices and policies, not on abstract labels. It also provides the doctrinal foundation for later cases involving electronic communications and devices in the public workplace, including City of Ontario v. Quon, and guides public entities in drafting and enforcing workplace policies that reduce privacy expectations and justify reasonable, targeted searches.