Here’s How Phone Metadata Can Reveal Your Affairs, Abortions, And Other Secrets - WaPo [View all]

[WillyT]

Here’s how phone metadata can reveal your affairs, abortions, and other secrets
By Timothy B. Lee - WaPo
Published: August 27 at 11:12 am

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The American Civil Liberties Union is challenging the National Security Agency’s dragnet surveillance of Americans’ phone calling records. On Monday, the ACLU asked the court to issue a preliminary injunction halting the program while its legality is litigated.

The program only collects metadata about Americans’ phone calls—who they call, when, and how long the calls last. In defending the program, the government has cited a controversial 1979 Supreme Court decision that held that phone records are not protected by the Fourth Amendment because consumers do not have a reasonable expectation of privacy in their calling records.

But Ed Felten, a professor of computer science at Princeton University (and, full disclosure, my former graduate school advisor) argues that this intuition is wrong. In a legal brief supporting the ACLU’s request, Felten argues that the distinction between call “contents” and “metadata” isn’t always clear. Sometimes, the mere fact that someone called a particular number reveals extremely sensitive personal information.

Certain telephone numbers are used for a single purpose, such that any contact reveals basic and often sensitive information about the caller. Examples include support hotlines for victims of domestic violence and rape, including a specific hotline for rape victims in the armed services.

Similarly, numerous hotlines exist for people considering suicide, including specific services for first responders, veterans, and gay and lesbian teenagers. Hotlines exist for suffers of various forms of addiction, such as alcohol, drugs, and gambling.

Similarly, inspectors general at practically every federal agency—including the NSA—have hotlines through which misconduct, waste, and fraud can be reported, while numerous state tax agencies have dedicated hotlines for reporting tax fraud. Hotlines have also been established to report hate crimes, arson, illegal firearms and child abuse. In all these cases, the metadata alone conveys a great deal about the content of the call, even without any further information.

And, Felten argues, metadata becomes even more revealing when it’s collected in bulk:

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More: http://www.washingtonpost.com/blogs/the-switch/wp/2013/08/27/heres-how-phone-metadata-can-reveal-your-affairs-abortions-and-other-secrets/