Digital footprints left behind in anonymous email accounts ultimately exposed the affair between CIA director David Petraeus and his biographer Paula Broadwell. It started with threatening emails that were sent to Jill Kelley from an anonymous e-mail account. Kelley works as a volunteer social planner for events at MacDill Air Force Base in Tampa, Fla., which is where Petraeus was a commander from 2008 until 2010. The FBI determined that the emails sent to Kelley belonged to Broadwell. Investigators then uncovered other email addresses that had been sent from that computer, including sexually explicit e-mails that Broadwell exchanged with another person with an anonymous email, who turned out to be Petraeus.
According to an article on Wired, email accounts contain information in the metadata of e-mail headers that can be used to track down additional details.
Google also cooperates with government requests for data. As a result, Broadwell will most likely become part of the statistics that Gmail reports in its next transparency report. According to Wired:
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