Category Archives: Secrecy and Government

More Reason’s to Turn Off Your Smartphone

November 2014 was an exceptional month on the government surveillance front.  Some new acronyms and codewords entered the lexicon of discussion such as IMSI catcher, Dirtbox, and Stingray.

The first time I heard the term IMSI catcher was actually in late October.  This was in a segment by Martin Kaste on the October 22nd broadcast of All things Considered.  Kaste was speaking with an ACLU attorney named Nate Freed Wessler.  IMSI is an acronym for International Mobile Subscriber Identity. So what’s an IMSI catcher?  The idea is this: a transciever is designed to mimic a local cellphone tower.  Essentially, it spoofs all phones within its range into thinking its the nearest cell tower and so the phones exchange data with it, such as their location. What Wessler had tried to do was use Florida’s public records act to get information about what a police department in Sarasota was doing with their IMSI catchers.  Wessler’s tale ended with the U.S. Marshall’s Service seizing the collected records before they could be turned over.

This red-lined my curiosity.  I emailed the article to several colleagues, some of whom were dismayed to find an attachment in their email marked “IMSI Catcher.”  I had to find out more about this topic and began researching it in my spare time.  Turns out that Devlin Barrett of the Wall Street Journal was way ahead of me.  His story bore the ominous title “American’s Cellphones Targeted in Secret U.S. Spy Program.” It was published on November 13th and can be found here.  I heard about it the following day, again on NPR, this time in a segment by Audie Corniche.  She did a brief interview with Devlin.  When I realized what they were talking about, I couldn’t believe my ears. The U.S. Marshall’s Service had installed very powerful IMSI catchers in Cessna airplanes and were using them in the course of their investigations. This activity could collect data from potentially thousands of phones and raised a number of disturbing questions.  What do they do with the data of the people they aren’t looking for?  Where are the warrants and the court orders authorizing this dragnet?

The device deployed by the Marshall’s is informally called a “Dirtbox” and derived from the acronym of the manufacturer DRT or Digital Receiver Technology.  That company is now a subsidiary of Boeing, an operation that has produced some of the finest military surveillance aircraft.

In contrast, a Stingray is a device with a shorter range that operates on the ground.  It essentially performs the same function on a smaller scale.  Turns out our own Houston Police Department acquired one or more of these devices recently and uses them in investigations.  This was discovered by KPRC investigative reporter Jace Arnold and published on November 19th.  Chief Charles McClelland assured Arnold that HPD always gets judicial approval for its surveillance activity.  My question is, have they ever been compelled to disclose this kind of surveillance to a particular defendant’s lawyer?

It seems to me the next logical step would be to place a DRT, or even a Stingray, into a drone.  If I’ve thought of that sitting here at my desk, I’m sure someone else already has.

AWACS 1988“Skyking, Skyking…..”  The majestic Boeing E-3 Sentry.

“Car 54, Where are you?”


That’s a good question.  What the defense usually wants to know is: “What was Car 54’s location at a certain time on the night the defendant was arrested?”  Fortunately, there is a way to  find this out.  Most modern police prowlers are equipped with electronics that report their location to a central command center.  (For example, the Houston Emergency Center.)

Global Positioning System (GPS) satellites are utilized to keep dispatchers apprised of the current location of law enforcement and emergency vehicles. This kind of system is also known by the acronym “AVL” or automatic vehicle location. Such a system serves several purposes. It aids the dispatcher in responding to calls because they can see in real time who is close to a particular area or incident. It is an aid to managing events as well as protecting the safety of personnel in the field. In the sense of safety, its not unlike radar for air traffic controllers. If you disappear from the screen, its likely that something is very wrong.This system also serves other purposes unstated in the official description. It allows resourceful lawyers and investigators to reconstruct who was where after the fact. These location records have been used in that manner by both defense lawyers and prosecutors.  It can provide a certain degree of accountability and oversight of the activity of police officers.

This is all fine and well. The fact that such records exist is of no consequence unless you can obtain them. To their great credit, the Houston Emergency Center will timely respond to requests for AVL records whether through a Public Information Act request or a subpoena.

Harris County however is another matter. With respect to the County it seems that we have is another collision of secrecy vs. accountability and transparency.
County authorities have generally stonewalled the efforts of lawyers and investigators to obtain AVL data. We have tried multiple Public Information requests as well as subpoenas to get at them. At this point, I am not certain who the custodian of these records is or where the command and control center that uses them is located. The other unknown is what is the retention period for these records? (Ideally it would be indefinite if there is a pending criminal investigation.)

Keep in mind these are public safety records generated by a system built with public funds that monitors public servants.  Below is a recent and interesting news story by KTRK reporter Ted Oberg on this topic:

“GPS units in law enforcement vehicles: What some lawmen, lawmakers want to keep you from seeing.”

I would like to thank Mark Bennett for bringing this particular story to my attention. Mark has been very actively involved in the effort to obtain AVL records from Harris County.