"A New Business in the World": The Telegraph, Privacy, and the U.S. Constitution in the Nineteenth Century.

Disclosures about electronic surveillance by the U.S. National Security Agency have revived interest in issues of communications privacy and Fourth Amendment rights. In the early days of the telegraph, there was no legal protection afforded to the privacy of telegraphic communication, and seizures of telegraphic dispatches figured in major events of the nineteenth century in the United States. Attempts to protect the content of telegrams by defining a customer/operator "privilege" under common law were rejected by the courts, as were attempts to protect the confidentiality of telegraphic communications through an analogy with the postal service. Each attempt by the government and the courts to obtain access to private telegraphic communication revived a debate about the constitutionality of such actions, which ultimately led to a new interpretation of constitutional law, including a legal right to privacy.