Justice  /  Journal Article

The Post Office and Privacy

We can thank the postal service for establishing the foundations of the American tradition of communications confidentiality.

In the early years of the American republic, the most prominent arm of the federal government was the post office. It wasn’t only the developing nation’s primary communications network: the national postal service was laying the foundations of the American tradition of communications confidentiality. These foundations were set a century before the Supreme Court began to interpret the Fourth Amendment as applying to private, personal communications, and long before there were any kinds of wires to tap.

Digital technologies have much reduced letter-writing, but the heritage of mail free from unreasonable or warrantless searches or surveillance has been extended into the digital realm.

If today we see the principle of communications privacy as fundamental to the Fourth Amendment,” writes legal scholar Anuj C. Desai, “we have postal policymaker to thank, for it was through the post office, not the Constitution or the Bill of Rights, that early Americans first established that principle.”

Desai notes that the modern interpretation of the Fourth Amendment proscribing “warrantless ‘wiretapping’—intercepting a communication while the communication is taking place” dates to two 1967 Supreme Court decisions, Berger v. New York and Katz v. United States. These cases, which declared warrantless tapping of phone lines illegal, overturned the four-decade old precedent of Olmstead v. United States (1928). Olmstead allowed warrantless wiretapping of phones, but the “intellectual underpinnings” of the 1967 decisions stemmed from Justice Louis Brandeis’s famous dissent in Olmstead, in which he wrote that “to protect that right [to be let alone], every unjustifiable intrusion by the Government upon the privacy of the individual, whatever the means employed, must be deemed a violation of the Fourth Amendment.”

As Desai shows, Brandeis’s dissent had intellectual underpinnings in the Supreme Court’s 1878 Ex parte Jackson decision. Jackson was the first “case in which the Court ruled that the Fourth Amendment preserved a realm of communications privacy from government intrusion.” The Fourth Amendment makes no mention of communications, but in Jackson, the Court declared that the “Fourth Amendment precluded the government from opening sealed letters without a warrant.”

As it happened, that was post office policy from the beginning of the US Postal Service. The Post Office Act of 1792, the first major postal law enacted after the adoption of the Constitution in 1789, banned the opening of letters.