In re Application of The U.S. For Historical Cell Site Data.

• Decision Date: 29 October 2010
• Docket Number: Nos. H–10–998M, H–10–990M, H–10–981M.,s. H–10–998M, H–10–990M, H–10–981M.
• Citation: 747 F.Supp.2d 827
• Parties: In re Application of the UNITED STATES of America FOR HISTORICAL CELL SITE DATA.
• Court: U.S. District Court — Southern District of Texas

747 F.Supp.2d 827

In re Application of the UNITED STATES of America FOR HISTORICAL CELL SITE DATA.

Nos. H–10–998M, H–10–990M, H–10–981M.

United States District Court, S.D. Texas, Houston Division.

Oct. 29, 2010.

Eric Darnell Smith, James L. Turner, Office of the US Attorney, Houston, TX, for Plaintiff.

OPINIONSTEPHEN WM. SMITH, United States Magistrate Judge.

In three separate criminal investigations earlier this month, this court denied the Government's request under the Stored Communications Act (SCA) to compel cell phone service providers to produce cell site information for target cell phones. Among other things, each application sought “records or other information pertaining to subscriber(s) or customer(s), including historical cell site information and call detail records (including any two-way radio feature mode) for the sixty (60) days prior to the date the Order is signed by the Court (but not including the contents of communications).” ¹ Each application identically defined the requested information as “the antenna tower and sector to which the cell phone sends its signal,” specifically including “the cellsite/sector(s) used by the mobile telephone to obtain service for a call or when in an idle state.” In other words, the Government seeks continuous location data to track the target phone over a two month period, whether the phone was in active use or not.

This court has previously granted such requests.² However, recent months have brought to light important developments in both technology and caselaw raising serious constitutional doubts about such rulings. Accordingly I denied these requests, but invited the Government if it disagreed to submit a brief to justify its position with appropriate legal and factual support, which it has now done.³

Five years ago the first reported decisions on government acquisition of cell site information from telephone companies appeared.⁴ The focus of those early decisions was the appropriate legal standard for obtaining prospective location information under the Electronic Communications Privacy Act (ECPA). Thereafter, a handful of decisions addressed the related problem of law enforcement access to historical cell site data collected and maintained by providers over time. A few courts have held that such requests triggered the Fourth Amendment warrant requirement,⁵ but most courts to date have granted government access to such information under the SCA, which imposes a less-than-probable cause standard.⁶

Several weeks ago U.S. Magistrate Judge James Orenstein, who authored the very first cell site opinion, suggested in a new opinion ⁷ that courts re-examine the constitutionality of historical cell site requests in light of recent appellate court decisions, such as that of the District of Columbia Court of Appeals in United States v. Maynard.⁸ As if to underscore his point, two weeks later the Third Circuit became the first federal appellate court to issue an opinion dealing with government access to historical cell site data.⁹ Rather than definitively resolving the Fourth Amendment issue, the court remanded the case to the district court, concluding that the factual record was insufficient to resolve whether such records “could encroach upon ... citizens' reasonable expectations of privacy regarding their physical movements and locations.” ¹⁰

Though significant, the caselaw developments have been outstripped by advancing technology. Recently, committees in both the House and Senate have conducted hearings on proposals to update ECPA, the 1986 statute establishing the regulatory regime governing electronic communications. Expert testimony at those hearings reveals that regulatory and market forces have produced dramatic advances in location technology over the past half-decade. As will be shown, this new technology has altered the legal landscape even more profoundly than the new caselaw.

Mindful of the Third Circuit's admonition to base a Fourth Amendment adjudication on an adequate factual record, the court begins with the following findings of fact. These findings are based on judicially noticed facts derived from material contained in the record appendix, including publicly available industry studies, independent surveys, provider policies, and product specifications. The most significant findings are based on expert testimony recently given at a House Judiciary Subcommittee hearing entitled “ECPA Reform and the Revolution in Location Based Technologies and Services.” The purpose of this oversight hearing was not to consider a particular bill, but to educate Congress on the current state of location technology in the telecommunications industry, so that needed reforms to the 1986 statute could be identified, drafted, and debated.¹¹ Given that such testimony was not offered for partisan purposes or to advocate specific legislation, the court finds it particularly appropriate for judicial notice under Rule 201 of the Federal Rules of Evidence.¹²

Findings of Fact

Cell Phone Technology in General

1. Unlike conventional wireline telephones, cellular telephones use radio waves to communicate between the user's handset and the telephone network. ¹³

2. Cellular service providers maintain networks of radio base stations (“cell sites”) spread throughout their geographic coverage areas.¹⁴

3. A wireless antenna at each cell site detects the radio signal from the handset, and connects it to the local telephone network, the Internet, or another wireless network.¹⁵

4. Cell phones periodically identify themselves to a nearby base station as they move about the coverage area, a process called “registration.” The registration process is automatic, and occurs whenever the phone is on, without the user's input or control. The registration signal is carried over a channel separate from the channel used to carry the call itself.¹⁶

5. During a call, if the phone moves nearer to another base station, the call is “handed off” between base stations without interruption.¹⁷

6. No longer just big three-sided radio towers, base station antennas can be mounted outdoors on roof-tops, building-sides, trees, flagpoles, and church steeples, or indoors in homes and offices. Many are no larger than a conventional stereo speaker.¹⁸

Wireless Location Technology

7. There are two distinct technological approaches for fixing the location of a cell phone: handset-based (GPS) and network-based (cell site). ¹⁹

8. GPS is the acronym for Global Positioning System, which is comprised of at least 24 satellites constantly orbiting the earth in six low earth orbits. ²⁰

9. For GPS location, special hardware in a user's handset receives signals from at least four global position satellites, allowing the handset to calculate its latitude and longitude whenever it is in unobstructed satellite range.²¹

10. Current GPS technology can achieve spatial resolution typically within ten meters.²²

11. Despite its relative precision, GPS has at least three fundamental drawbacks as a location tool: (a) it is not available for all handset models, especially older models; (b) it works reliably only outdoors, when the handset has an unobstructed view of several GPS satellites in the sky above; and (c) perhaps most significantly, it can be disabled by the user.²³

12. For these reasons, GPS is neither the most pervasive nor the most generally applicable phone location system, especially for surveillance purposes.²⁴

13. For network-based location, the position of the phone is calculated by the network based on data collected and analyzed at the cell site receiving the phone's signals, without explicit assistance from the user or his handset. ²⁵

14. A variety of techniques may be used for network-based location. The most basic technique is to identify the particular base station (or sector) with which the phone was communicating every time it makes or receives a call and when it moves from one sector to another.²⁶

15. The relative precision of cell site location depends on the size of the cell sector. The smaller the sector, the more precise the location fix. ²⁷

16. In early cellular systems, base stations were placed as far apart as possible to provide maximum coverage. At that time, a sector might cover an area several miles or more in diameter. Today this is true only of sparsely populated, rural areas.²⁸

17. Due to a combination of factors, the size of the typical cell sector has been steadily shrinking in recent years.²⁹

18. As the density of cellular users grows in a given area, the only way for a carrier to accommodate more customers is to divide the coverage area into smaller and smaller sectors, each served by its own base station and antenna. ³⁰

19. New services such as 3G Internet create similar pressure on the available spectrum bandwidth, again requiring a reduction in the geographic size of sectors.³¹

20. Another factor contributing to smaller sector size is consumer demand for more reliable coverage in areas with unfavorable radio conditions ( e.g., elevators), which again requires additional base stations to cover such “dead spots.” ³²

21. The number of cellular base stations in the U.S. has tripled over the last decade, and the rate of growth is accelerating. By one industry estimate, there are now over 251,000 reported cell sites operating in the United States. There were only 913 the year before ECPA was passed.³³

22. The trend toward smaller cell sectors has accelerated with the deployment of smaller-scale base stations designed to serve very small areas such as particular floors of buildings, or individual homes and offices. ³⁴

23. This new generation of cellular base station is generally known as a “microcell,” and smaller versions are sometimes referred to as a “picocell” or “femtocell.” ³⁵

24. Microcell technology is increasingly used by many carriers, including AT & T, Verizon, and Sprint. A microcell has a range of 40 feet (12 meters). ³⁶

25. The effect of this trend toward...