Ladar Levison, founder of encrypted email service Lavabit, discusses recent government action that led him to shut down his firm. When it was suspected that NSA whistleblower Edward Snowden used Lavabit’s email service, the FBI issued a National Security Letter ordering Levison to hand over SSL keys, jeopardizing the privacy of Lavabit’s 410,000 users. Levison discusses his inspiration for founding Lavabit and why he chose to suspend the service; how Lavabit was different from email services like Gmail; developments in his case and how the Fourth Amendment has come into play; and his involvement with the recently-formed Dark Mail Technical Alliance.