The Drug Enforcement Administration formerly maintained a secret database of Americans’ telephone calls to some foreign countries, the Justice Department revealed this week. A document filed by the department in a criminal case on Thursday revealed that the agency collected details about Americans’ calls to certain countries believed to be closely linked to drug trafficking networks. The program is different from a more well-known database maintained by the National Security Agency (NSA), though it appears similar in some respects. According to the government’s brief, the DEA tracked information about phone calls from the United States to other “designated” countries that...