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Feds Can Locate Cell Phones Without Telcos

schwit1 sends along an Ars Technica report covering the release of documents obtained under the FOIA suggesting that the Justice Department may have been evading privacy laws in their use of "triggerfish" technology. Triggerfish are cell-tower spoofing devices that induce cell phones to give up their location and other identifying information, without recourse to any cell carrier. "Courts in recent years have been raising the evidentiary bar law enforcement agents must meet in order to obtain historical cell phone records that reveal information about a target's location. But documents obtained by civil liberties groups under a Freedom of Information Act request suggest that 'triggerfish' technology can be used to pinpoint cell phones without involving cell phone providers at all. The Justice Department's electronic surveillance manual explicitly suggests that triggerfish may be used to avoid restrictions in statutes like CALEA that bar the use of pen register or trap-and-trace devices..." The article does mention that the Patriot Act contains language that should require a court order to deploy triggerfish, whereas prior to 2001 "the statutory language governing pen register or trap-and-trace orders did not appear to cover location tracking technology."

2 of 199 comments (clear)

  1. Re:batteries ftw by Fastolfe · · Score: 5, Informative

    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...

    Do elaborate, please. RFID does, in fact, require power. It's just that that power is provided by the reader when in proximity to the tag. Are you suggesting there are RFID tags embedded into "modern cell phones"? Or something else? If you're suggesting that cell towers have the ability to blanket a region with an electric field capable of getting all of the cell phones to respond (loudly enough) to a "ping" for their location, I'm afraid I'm going to have to call BS. So what is this "functionality" that you claim allows cell phones to be identified and located without a battery?

  2. Re:batteries ftw by IorDMUX · · Score: 5, Informative

    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...

    I am a cell phone designer, and a phone reporting *anything*, even just a handshake, to a tower thousands of meters away takes significant power.

    It is possible that the little coin cell battery in most phones could handle the receiving of a signal, and then wake the phone up and have it reply with the main battery, (though to the best of my knowledge we don't let phones do that [and yes, I design power systems]), but if the main battery isn't there, that's a no-go.

    Passive RFID is a completely different batch of apples than active cellular communications. Passive RFID has a maximum range of around 10 meters (phased array antennas notwithstanding, but seriously...). You would need a specially designed phone to use some sort of active RFID when the battery is removed, and we don't make those.

    Now, this isn't to say that I'm not pissed at the Feds for doing something like this--perhaps even more so than the average user. I can see how they are taking advantage of perfectly innocuous and functional code and systems designed by my co-workers to agreed standards, and then using those standards to make our customers lose their privacy.

    *sheesh*

    --
    >> Standing on head makes smile of frown, but rest of face also upside down.