The Cyberlaw Clinic filed an amicus brief in the Supreme Judicial Court on behalf of the American Civil Liberties Union Foundation of Massachusetts, the American Civil Liberties Union Foundation, and the Electronic Frontier Foundation in the case of Commonwealth v. Gelfgatt, SJC No. 11358. In the brief, we argue that the Fifth Amendment and article 12 of the Massachusetts Declaration of Rights prohibit the government from compelling a defendant to decrypt their electronic data for use against them in criminal proceedings because it involves the kind of testimonial acts protected by constitutional protections against self-incrimination. This is the Cyberlaw Clinic’s third brief filed in a series of cases before the Supreme Judicial Court addressing updates to constitutional protections in light of new technologies. Prior filings on behalf of the Electronic Frontier Foundation concerned warrant requirements for GPS tracking of suspects (Commonwealth v. Rousseau) and historical cell phone location records (Commonwealth v. Augustine).