Wired's Kevin Poulsen has pried loose details about the FBI's homebrew spyware, used in criminal investigations. The document is redacted almost to the point of uselessness, but there are some interesting nuggets. Paul Ohm, who used to work in the FBI department responsible for the spyware, notes,

Page one may be the most interesting page. Someone at CCIPS, my old unit, cautions that "While the technique is of indisputable value in certain kinds of cases, we are seeing indications that it is being used needlessly by some agencies, unnecessarily raising difficult legal questions (and a risk of suppression) without any countervailing benefit,"

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On page 152, the FBI's Cryptographic and Electronic Analysis Unit (CEAU) "advised Pittsburgh that they could assist with a wireless hack to obtain a file tree, but not the hard drive content." This is fascinating on several levels. First, what wireless hack? The spyware techniques described in Poulsen's reporting are deployed when a target is unlocatable, and the FBI tricks him or her into clicking a link. How does wireless enter the picture? Don't you need to be physically proximate to your target to hack them wirelessly? Second, why could CEAU "assist . . . to obtain a file tree, but not the hard drive content." That smells like a legal constraint, not a technical one. Maybe some lawyer was making distinctions based on probable cause?