A story at Ars Technica describes yet another Federal database of logged call details maintained by the Federal government which has now come to light, this one maintained by the Department of Justice rather than the NSA, and explains how it came to be discovered:
[A] three-page partially-redacted affidavit from a top Drug Enforcement Agency (DEA) official, which was filed Thursday, explained that the database was authorized under a particular federal drug trafficking statute. The law allows the government to use "administrative subpoenas" to obtain business records and other "tangible things." The affidavit does not specify which countries records were included, but specifically does mention Iran. ... This database program appears to be wholly separate from the National Security Agency’s metadata program revealed by Edward Snowden, but it targets similar materials and is collected by a different agency. The Wall Street Journal, citing anonymous sources, reported Friday that this newly-revealed program began in the 1990s and was shut down in August 2013. From elsewhere in the article:
"It’s now clear that multiple government agencies have tracked the calls that Americans make to their parents and relatives, friends, and business associates overseas, all without any suspicion of wrongdoing," [said ACLU lawyer Patrick Toomey]. "The DEA program shows yet again how strained and untenable legal theories have been used to secretly justify the surveillance of millions of innocent Americans using laws that were never written for that purpose."