Over Redaction in Audit of FBI’s Use of Illegal Exigent Letters

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The report reveals that AT&T routinely provided the FBI with the “community of interest” profiles of its customers without any legal process. However, the DOJ redacted a large section of the report that discusses what a “community of interest” is, including an explanatory diagram. Yet, AT&T itself has published several research papers extensively discussing communities of interest. Basically, your community of interest includes the people you call and who call you, and the people with whom this group communicates. It is sometimes refined by frequency or by time period. AT&T even published the Hancock programming language, which AT&T designed to analyze communities of interest, and “sift calling card records, long distance calls, IP addresses and internet traffic dumps, and even track the physical movements of mobile phone customers as their signal moves from cell site to cell site.” AT&T published this graphic, which illustrates AT&T using what they call “guilt by association” to determine fraud within a community of interest (the shaded boxes).

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