"Bnited States Senate
WASHINGTON, DC 20510
October 6, 2016
The Honorable Tom Wheeler
Chairman
Federal Communications Commission
445 12th Street SW
Washington, DC 20554
Dear Chairman Wheeler:
We write regarding recent reports about state and local law enforcement's use of "cell
site simulators"—portable surveillance devices that collect cell phone identification and location
information by mimicking cellphone towers. We are particularly concerned about allegations that
cell site simulators—commonly referred to as "Stingrays"—disrupt cellular service and may
interfere with calls for emergency assistance, and that the manner in which cell site simulators
are used may disproportionately impact communities of color. While we appreciate law
enforcement's need to locate and track dangerous suspects, the use ofStingray devices should
not come at the expense of innocent Americans' privacy and safety, nor should law
enforcement's use of the devices disrupt ordinary consumers' ability to communicate.
Recent complaints filed with the Federal Communications Commission (FCC) have
alleged that state and local law enforcement agencies' use ofStingray devices violate the
Communications Act1 Specifically, the complaints allege that cell site simulators' disruption of
cell phones' ability to make and receive calls, possibly including calls to 911 and other
emergency responders, constitutes "willful" interference with a communications network, which
is prohibited by Section 333 of the Communications Act. The complaints further assert that state
and local enforcement agencies do not possess the requisite licenses to operate Stingray devices
over wireless specb-um—licenses required by Section 301 of the Communications Act. Reliable
access to telecommunications services is vital to Americans' ability to communicate and
successfully engage in today s economy, and it is the FCC's responsibility to ensure that
communications services are available to Americans of all backgrounds.
We are also concerned by the complaints' assertion that cell site simulators are more
frequently used in minority neighborhoods. Section 151 of the Communications Act tasks the
FCC with the duty to ensure that people of the United States are able to access communications
"without discrimination on the basis of race, color, religion, national origin, or sex." We have
long been concerned that underlying inequities within our criminal justice system have a
disproportionate impact on minority communities. Law enforcement practices that excessively
subject communities of color to heightened and potentially unlawful government surveillance
only exacerbate this concern. In this instance, there is also a possibility that the surveillance
Complaint for Relief Against Unauthorized Radio Operation and Willful Interference with Cellular
Communications, In re Baltimore City Police Dep 't, Baltimore, Md (filed Aug. 16, 2016),
https://ecfsapi.fcc.gov/file/l 0816659216934/CS%20Simulators%20Comp!aint%
20FINAL.pdf; Memorandum in Support of Complaint for Relief Against Unauthorized Radio Operation and Willful
Interference with Cellular Communications and Petition for an Enforcement Advisory on Use of Cell Site
Simulators by State and Local Government Agencies, In re Baltimore City Police Dep 7, Baltimore, Me! (filed Sept.
1, 2016),https://www.aclu.org/sites/default/files/field_documenb/aclu-eff_fcc_cell_site_simulator_filing.pdf
827
technology may more frequently interfere, however inadvertently, with the ability of minority
communities to use wireless communications and emergency services. Such interference raises
additional questions where federal funding appears to have supported the acquisition of this
technology by state and local law enforcement. We urge the PCC to investigate and, if
necessary, address the charges in the referenced complaints. In addition, we urge that the
findings of such an investigation be made public.
Finally, we write to request additional information about the FCC's role in overseeing the
use of cell site simulators. The Was^mgton Post recently reported some confusion within the
agency regarding how the devices operate. According to the Post article, an FCC official
indicated that cell site simulators do not transmit signals on the wireless spectrum—a statement
directly at odds with Department of Justice documentation on the devices.3 In an effort to gain a
better understanding of how Stingrays may be interfering with consumers' ability to
communicate, we respectfully request that you respond to the following questions:
1. Do cell site simulators, including but not limited to the Stingray and HailStorm models,
transmit over frequencies licensed to cellular phone carriers? What is the power and
range of these devices' transmissions?
2. Does the Communications Act require that law enforcement agencies obtain licenses
from the FCC to transmit over licensed spectrum, and refrain from causing harmful
interference? Please provide any examples of devices for which law enforcement has
acquired a license in order to transmit over licensed spectrum. Are such agencies required
to coordinate with the spectrum holder in any way?
3. For devices that do require a license in order to transmit over licensed spectrum, what
steps can the FCC take to hold users accountable for operating the devices without the
appropriate license? What procedures are currently in place to verify that users have
acquired the appropriate license prior to using a device? If the FCC does not cuirently
See Memorandum from Detective Jeffrey Shipp, Tacoma Police Department to Kathy Katterhagen, Procurement
and Payables Manager, City ofTakoma (Mar. 3,2013), https://www.docLimentcloud.org/documents/1280700-
unredacted-purchmemo-hailstorm.html (explaining that the Tacoma Police Department acquired cell site simulator
technology in 2007 using a DOJ Law Enforcement Grant award, and that in 2013 the Department received a
Department of Homeland Security Port Security Grant in order to update its existing cell site simulator technology);
Letter from William J. Qumlan, General Counsel, Office of the Illinois Governor, to Larry G. Trent, Director,
Illinois State Police (Mar. 18, 2008), https;//muckrock.s3.amazonaws.com/foia_files/l4-075;:l_Docs.pdfat 7 (stating
that funding for Illinois State Police's purchase of cell site simulator technology "is provided by the Homeland
Security Grant").
3 Ellen Nakashima, Civil Liberties Groups Ask FCC to Probe Balfimof'e Police Use ofCellp/wne Trackmg Devices,
WASH. POST (Aug. 16,2016), https://www.washingtonpost.com/world/
national-security/civil-liberties-groups-ask-fcc-to-probe-baltimore-police-use-of-cell-phone-tracking-
devices/2016/08/16/37002b76-6336-l le6-96c0-37533479f3f5_story.html ("The official, who spoke on the
condition of anonymity because she was not authorized to talk on the record, said at one point that the devices do
not transmit on the wireless spectrum—which experts dispute."); contra U.S. DEP'T OF JUSTICE, DEPARTMENT OF
JUSTICE POLICY GUIDANCE: USE OF CELL-SITE SIMULATOR TECHNOLOGY,
https://www.justice.gov/opa/file/767321/download ("Cell-site simulators, as governed by this policy, function by
transmitting as a cell tower."),
have such procedures in place, when will the agency develop oversight procedures and
what will these procedures consist of?
4. Are cell site simulators capable of disrupting cellular communications in their vicinity?
To the extent that the answer is yes, how large is the area of interference, and does the
interference extend to 911 calls, or calls to police, hospitals, or public safety hotlines?
5. As part of the equipment authorization process for cell site simulators, has the FCC
determined that cell site simulators do not cause harmful interference? When was the last
time a cell site simulator went through the equipment authorization process?
6. Including any testing that may have been conducted in the equipment authorization
process, has the FCC ever tested cell site simulators in a real world setting to determine
whether the devices disrupt a cell phone's ability to make or receive calls? If so, when?
7. Does the FCC maintain a record of which state and local law enforcement agencies
possess cell site simulators, how many each department has, and when, where, and for
how long the devices are used?
8. Does the FCC have any knowledge of whether state and local police departments take
steps to ensure cell site simulators are used in a way that minimizes network interference,
protects emergency calling, and does not disproportionately harm communities of color?
9. What is the current status of the task force that the FCC established in 2014 to study
reported misuse of surveillance technology? How often has this task force met? Please
provide us with the results of any studies it has undertaken as well as a description of its
actions to combat misuse of surveillance technologies.
10. The equipment authorization granted to the manufacturer ofStingrays requires states and
localities to advance coordinate with the FBI before acquiring or using cell site
simulator equipment. Publicly available documents indicate that the FBI implements this
coordination requirement by requiring state and local agencies to sign a non-disclosure
agreement with the FBI. For example, one letter from the FBI to a local law enforcement
agency states, [c]onsistent with the conditions of the equipment authorization granted to
4 Letter from Chairman Wheeler, FCC to U.S. Rep. Alan Grayson (Aug. 1, 2014),
https://apps.fcc.gov/edocs_public/attachmatch/DOC-328995Al.pdf("I have recently established a task force to
initiate immediate steps to combat the Illicit and unauthorized use of IMSI catchers. The mission of this task force is
to develop concrete solutions to protect the cellular network systemicaHy from similar unlawful intrusions and
interceptions.").
5 See, e.g., FCC, Grant of Equipment Authorization, Harris Corporation, FCC Identifier
NK73166210 (Mar. 2, 2012),
https://apps.fcc.gov/oetcf/eas/reports/Eas731GrantForm.cfm?mode=COPY&RequestTimeout=5
00&application_id=S02SFOCotzKlbdYCDPFHA%3D%3D&fcc_id=NK73166210; FCC, Grant
of Equipment Authorization, Harris Corporation, FCC Identifier NK73092523 (Apr. 19, 2011),
ht4>s://apps.fcc.gov/oetcf/eas/reports/Eas731GrantForm.cfm?mode=COPY&RequestTimeout=5
00&application_id=9nDFvP9N200RJUhSYM6ASQ%3D%3D&fcc_id=NK73092523.
[the manufacturer] by the [FCC], state and local law enforcement agencies must
coordinate with the [FBI] to complete [a] non-disclosure agreement."
a. Did the FCC intend for its equipment authorizations for cell site simulators to
require that state and local law enforcement officials sign non-disclosure
agreements? If so, please explain why the grant of an equipment authorization is
conditioned on compliance with a non-disclosure agreement.
b. Has the FCC communicated with the FBI about the terms ofnon-disclosure
agreements as they relate to equipment authorizations? Has the FCC
communicated with the FBI or any other law enforcement agency about taking
steps to minimize network interference and protect calls to emergency services
while operating cell site simulators?
As always, thank you for your consideration of our request, and we look forward to
working with you to protect Americans privacy and safety.
Sincerely,
Al Franken
United States Senator
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JenRon Wy d 
United States Senator
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Edward J. Markey<
United States Senator
Patrick Leahy
United States Senator
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Shen'od Brown
United States Senator
Elizabelh Warren
United Btates Senator
FBI Non-Disclosure Agreement (June 29,2012), availabfe at http'y/www.nyclu.org/fiIes/releases/Non-Disclosure-
Agreement.pdf.
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Tom Udall
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Christopher A. Coons
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