Since 2009, U.S. Customs and Border Protection agents have been allowed to search electronic devices carried by citizens or noncitizens as they cross the border into the United States from other countries. More recently, Homeland Security Secretary John Kelly suggested this digital vetting should also include harvesting social media passwords. Kelly’s proposal prompted legal and technology experts to respond with an open letter expressing deep concern about any policy that demands that individuals violate the “first rule of online security”: Do not share your passwords.