In this Essay, I argue that civil discovery rules compelling the production of private papers violate the Fourth Amendment’s prohibition against unreasonable searches. A “search” occurs when a government agent intrudes upon a sphere in which society recognizes “a reasonable expectation of privacy.” Implicit in this definition is an affinity for private papers such as letters and diaries. Creators of such media possess a reasonable expectation of privacy in their contents. Thus, when police seek to examine such documents to look for evidence of crime, they usually must obtain a search warrant. For the warrant to issue, the police must establish probable cause. Conversely, under the Federal Rules of Civil Procedure and parallel state provisio...