Decryption Originalism: The Lessons of Burr

Abstract

The Supreme Court is likely to rule soon on how the Fifth Amendment privilege against
self-incrimination applies to compelled decryption of a digital device. When the Court
rules, the original understanding of the Fifth Amendment may control the outcome. This
Article details an extraordinary case that illuminates the original understanding of the
privilege and its application to compelled decryption. During the 1807 treason trial of
Aaron Burr, with Chief Justice John Marshall presiding, the government asked Burr’s
private secretary if he knew the cipher to an encrypted letter Burr had sent to a coconspirator. Burr’s secretary invoked the privilege against self-incrimination, leading to
an extensive debate on the meaning of the privilege and an opinion from the Chief Justice.

The Burr dispute presents a remarkable opportunity to unearth the original understanding
of the Fifth Amendment and its application to surprisingly modern facts. The lawyers in
Burr were celebrated and experienced advocates. The Chief Justice allowed them to argue
the Fifth Amendment question in exhaustive detail. And an attorney recorded the entire
argument in shorthand, including dozens of legal citations to the specific pages of the
authorities the lawyers invoked. The rich materials allow us to reconstruct for the first
time precisely how the privilege was understood by leading lawyers and Chief Justice John
Marshall soon after the Fifth Amendment’s ratification. The Article presents that
reconstruction, and it concludes by applying Burr’s lessons to the modern problem of
compelled decryption of digital devices such as cell phones and computers.

Keywords: Fifth Amendment, self-incrimination, originalism, encryption

JEL Classification: K14, K42