Cryptic Commons workshop - video 3 of 18 -  Sarah Scheffler
Channel: Cryptic Commons
Date: 2021-10-28

Sarah Scheffler, 
PhD candidate, Boston University: 
“A cryptographic view of "foregone conclusions" in compelled self-incrimination"

Abstract: The information security community has devoted substantial effort to the design, development, and universal deployment of strong encryption schemes that withstand search and seizure by computationally-powerful nation-state adversaries. In response, governments are increasingly turning to a different tactic: issuing subpoenas that compel people to decrypt devices themselves, under the penalty of contempt of court if they do not comply. Compelled decryption subpoenas sidestep questions around government search powers that have dominated the Crypto Wars and instead touch upon a different (and still unsettled) area of the law: how encryption relates to a person's right to silence and against self-incrimination.In this work, we provide a rigorous, composable definition of a critical piece of the law that determines whether cryptosystems are vulnerable to government compelled disclosure in the United States. We justify our definition by showing that it is consistent with prior court cases. Under our definition, decryption is generally not compellable. However, we show that many techniques that bolster security overall can leave one more vulnerable to compelled disclosure. We hope this work will influence the design of future cryptographic primitives and contribute toward the legal debates over the constitutionality of compelled decryption.