In August 2011, 35 ACLU affiliates filed over 380 public records
requests with state and local law enforcement agencies to ask about
their policies, procedures and practices for tracking cell phones.
200 law enforcement districts responded and the responses have documented the extent of warrantless location tracking via cell phones and text messages.
Sign a petition to support warrant requirements for cell phone tracking (Geolocation Privacy and Surveillance Act, H.R. 2168 and S.1212)
Take a law enforcement course in how to do cell phone tracking.
Here is a brief synopsis of the findings:
"The ACLU received over 5,500 pages of documents from over 200 local
law enforcement agencies regarding cell phone tracking. The responses
show that while cell phone tracking is routine, few agencies
consistently obtain warrants. Importantly, however, some agencies do
obtain warrants, showing that law enforcement agencies can protect
Americans' privacy while also meeting law enforcement needs.
The government responses varied widely, and many agencies did not
respond at all. The documents included statements of policy, memos,
police requests to cell phone companies (sometimes in the form of a
subpoena or warrant), and invoices and manuals from cell phone
companies explaining their procedures and prices for turning over the
The overwhelming majority of the over 200 law enforcement
agencies that provided documents engaged in at least some cell phone
tracking — and many track cell phones quite frequently. Most
law enforcement agencies explained that they track cell phones to
investigate crimes. Some said they tracked cell phones only in
emergencies, for example to locate a missing person. Only 10 said they have never tracked cell phones.
Many law enforcement agencies track cell phones quite frequently. The practice is so common that cell phone companies have manuals for police
explaining what data the companies store, how much they charge police
to access that data, and what officers need to do to get it.
Most law enforcement agencies do not obtain a warrant to
track cell phones, but some do, and the legal standards used vary
widely. Some police departments protect privacy by obtaining
a warrant based upon probable cause when tracking cell phones.
Unfortunately, other departments do not always demonstrate probable
cause and obtain a warrant when tracking cell phones.
Police use various methods to track cell phones.
Most commonly, law enforcement agencies obtain cell phone records about
one person from a cell phone carrier. However, some police departments,
like in Gilbert, Ariz., have purchased their own cell phone tracking technology. Cell phone companies have worsened the lack of transparency by law enforcement by hiding how long they store location data. Cell phone companies store customers' location data for a very long time. According to the DOJ, Sprint keeps location tracking records for 18-24 months, and AT&T
holds onto them "since July 2008," suggesting they are stored
indefinitely. Yet none of the major cell phone providers disclose to
their customers the length of time they keep their customers' cell
tracking data. Mobile carriers owe it to their customers to be more
forthright about what they are doing.