City of Ontario v. Quon

The City of Ontario Police Department gave pagers to officers including Quon (plaintiff), with a policy reserving the right to monitor all network communications and warning employees they had no expectation of privacy, extended informally to text messages. After Quon repeatedly exceeded his monthly text limit, the department audited transcripts covering only the months with overages to determine whether the character limit itself needed raising, discovering most of Quon's messages during work hours were personal rather than work-related, leading to discipline. Quon sued, and while the district court found a reasonable expectation of privacy but no Fourth Amendment violation, the Ninth Circuit reversed, agreeing on the expectation of privacy but finding the audit unreasonable.