EFiled: Sep 28 2016 03:59PM EDT
Transaction ID 59624044
Case No. N16A-02-006 RRC
SUPERIOR COURT OF THE STATE OF DELAWARE

JONATHAN RUDENBERG,

)
)
Petitioner Below,
)
Appellant
)
)
v.
)
)
DELAWARE DEPARTMENT OF JUSTICE, )
THE CHIEF DEPUTY ATTORNEY
)
GENERAL & DELAWARE DEPARTMENT )
OF SAFETY AND HOMELAND SECURITY, )
DIVISION OF STATE POLICE,
)
)
Respondents Below,
)
Appellees.
)
)

Case No. N16A-02-006 RRC

STATEMENT OF INTEREST OF THE UNITED STATES
BENJAMIN C. MIZER
Principal Deputy Assistant Attorney General
MARCIA BERMAN
Assistant Branch Director
CAROL FEDERIGHI
Senior Trial Counsel
United States Department of Justice
Civil Division, Federal Programs Branch
20 Massachusetts Avenue N.W. Room 7122
Washington, D.C. 20530
Tel.: (202) 514-1903
E-mail: carol.federighi@usdoj.gov

 TABLE OF CONTENTS

PAGE
INTRODUCTION .......................................................................................................................... 1
BACKGROUND ............................................................................................................................ 3
I.

CELL SITE SIMULATORS ............................................................................................... 3

II. LIMITS ON ACCESS TO CELL SITE SIMULATOR TECHNOLOGY .......................... 4
III. RUDENBERG’S DELAWARE FOIA REQUEST ............................................................ 6
ARGUMENT .................................................................................................................................. 7
THE REDACTED INFORMATION IS EXEMPT FROM DISCLOSURE UNDER
DELAWARE FOIA SECTION 10002(l)(6) ............................................................................. 7
A. The Redacted Information is Specifically Exempted From Disclosure
by the Federal FOIA, 5 U.S.C. § 552 .............................................................................. 8
B. The Redacted Information is Specifically Exempted From Disclosure
by the Common Law Under the Law Enforcement Privilege ........................................ 12
CONCLUSION ............................................................................................................................. 15

i

 TABLE OF AUTHORITIES

CASES

PAGE(S)

American Civil Liberties Union v. United States Department of Justice,
655 F.3d 1 (D.C. Cir. 2011) ................................................................................................ 10, 11
American Civil Liberties Union v. United States Department of Justice,
No. 13-cv-03127-MEJ, 2015 WL 3793496 (N.D. Cal. Jun. 17, 2015)............................... 10, 11
Fisher v. United States Department of Justice,
772 F. Supp. 7 (D.D.C. 1991), aff’d, 968 F.2d 92 (D.C. Cir. 1992) ........................................... 8
Guy v. Judicial Nominating Commission,
659 A.2d 777 (Del. Super. 1995) ................................................................................................ 7
Hodai v. City of Tucson,
239 Ariz. 34, 365 P.3d 959 (Ariz. Ct. App. 2016) ................................................................ 2, 11
Kurdyukov v. United States Coast Guard,
657 F. Supp. 2d 248 (D.D.C. 2009) ............................................................................................ 8
People v. Michaels,
No. 5-140709-7 (Cal. Super. Ct., Contra Costa County) (orders dated Nov. 4, 2015
& Dec. 3, 2015) .................................................................................................................... 2, 13
Rigmaiden v. Federal Bureau of Investigation,
No. CV12-1605-DLR-BSB (orders dated Aug. 31, 2015 & Dec. 14, 2015) ..................... 1, 10
United States v. Garey, No. 5:03-CR-83,
2004 WL 2663023 (M.D. Ga. Nov. 15, 2004) .................................................................... 12, 13
United States v. Rigmaiden,
844 F. Supp. 2d 982 (D. Ariz. 2012) .............................................................................. 1, 12, 13

FEDERAL STATUTES
5 U.S.C. § 552 ................................................................................................................................. 8
5 U.S.C. § 552(b)(7)(E) .............................................................................................................. 2, 8
18 U.S.C. § 2512 ............................................................................................................................. 4
18 U.S.C. § 3127(3) .................................................................................................................... 3, 4
28 U.S.C. § 517 ............................................................................................................................... 1
47 U.S.C. § 301 ............................................................................................................................... 4
47 U.S.C. § 302(a) .......................................................................................................................... 4

ii

 STATE STATUTES
California Evidence Code § 1040 ................................................................................................. 13
California Evidence Code § 1040(b)(2) ........................................................................................ 13
Delaware Code, tit. 29, §§ 10001-10007 ........................................................................................ 6
Delaware Code, tit. 29, § 10002(l)(6) ................................................................................... 2, 7, 14
Delaware Code, tit. 29, § 10005(b) ................................................................................................. 6

iii

 INTRODUCTION
In this action, petitioner Jonathan Rudenberg seeks to compel disclosure under the
Delaware Public Records Act of sensitive information withheld by the Delaware State Police
(“DSP”) relating to its purchase and use of cell site simulator equipment. This submission by the
United States is made pursuant to 28 U.S.C. § 517, which authorizes the Attorney General of the
United States to send any officer of the Department of Justice to “attend to the interest of the
United States in a suit pending in the court of the United States, or in the court of a State, or to
attend to any other interest of the United States.” Although the United States is not a party to
this case, it has a direct interest in the protection of the information withheld by the DSP. Cell
site simulator technology is a key tool in the Federal Bureau of Investigation’s (“FBI’s”)
investigation, interdiction, and suppression of criminal and terrorist activity. Disclosure of even
minor details about this technology will jeopardize, if not vitiate, the ability of the FBI and the
larger law enforcement community to successfully deploy this valuable technology to locate
criminals and terrorists, and recover victims. And DSP’s purchase and use of cell site simulator
equipment is subject to a non-disclosure agreement with the FBI.
The information withheld by the DSP consists of sensitive, non-public information about
the makes and models of cell site simulator systems and components parts and software
purchased by DSP. Disclosure of this information could harm federal criminal and national
security investigations by allowing criminals and terrorists to piece together information about
cell site simulators’ use and capabilities and thereby develop methods to evade them. Based on
these concerns, courts have protected this type of information from disclosure, and this Court
should do so as well. See, e.g., United States v. Rigmaiden, 844 F. Supp. 2d 982 (D. Ariz. 2012);
Rigmaiden v. Fed. Bureau of Investigation, No. CV12-1605-DLR-BSB (D. Ariz.) (orders dated

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 Aug. 31, 2015 & Dec. 14, 2015); People v. Michaels, No. 5-140709-7 (Cal. Super. Ct., Contra
Costa County) (orders dated Nov. 4, 2015 & Dec. 3, 2015); Hodai v. City of Tucson, 239 Ariz.
34, 365 P.3d 959 (Ariz. Ct. App. 2016).
As explained further below, the withheld information is exempt from disclosure under
section 10002(l)(6) of the Delaware Freedom of Information Act (“Delaware FOIA”), Del. Code,
tit. 29, § 10002(l)(6). That provision defines a “public record” subject to release under the
Delaware FOIA as excluding “[a]ny records specifically exempted from public disclosure by
statute or common law.” Id. The information at issue here is exempted from public disclosure
under both a federal statute and federal common law. First, the information at issue is exempted
from release under the federal Freedom of Information Act, pursuant to exemption 7(E) of that
Act. 5 U.S.C. § 552(b)(7)(E). Exemption 7(E) protects from public disclosure information that
would reveal “techniques and procedures for law enforcement investigations or prosecutions” “if
such disclosure could reasonably be expected to risk circumvention of the law.” Id. The
information at issue here is such information. Second, this sensitive information about cell site
simulators would be protected from disclosure in criminal discovery under the “law enforcement
sensitive” common-law privilege. The information at issue is protected by this privilege because
it was supplied in confidence to the DSP regarding a sensitive law enforcement technique, and its
disclosure could decrease the effectiveness of the investigative technique in future cases.
In sum, the redacted information falls within the scope of § 10002(l)(6). Accordingly,
this Court should find that the DSP properly withheld the information at issue and should deny
Rudenberg’s petition seeking to compel disclosure of unredacted copies of the records at issue.

2

 BACKGROUND
I.

CELL SITE SIMULATORS
Law enforcement agents can use cell site simulators to help locate cellular devices whose

unique identifiers are already known to law enforcement, or to determine the unique identifiers
of an unknown device by collecting limited signaling information from devices in the simulator
operator’s vicinity. Declaration of Russell D. Hansen, Supervisory Special Agent, currently
assigned as the Chief, Tracking Technology Unit, FBI Operational Technology Division
(“Hansen Decl.”), ¶ 4. In general, cell site simulators function by transmitting as a cell tower,
thereby simulating a cell tower. Id. ¶ 5. In response to the signals emitted by the simulator,
cellular devices in the area of the device identify the simulator as the most attractive cell tower in
the area and thus transmit signals to the simulator that identify the device in the same way that
they would with a networked tower. Id.
A cell site simulator receives and uses an industry standard unique identifying number
assigned by a device manufacturer or cellular network provider. Hansen Decl. ¶ 6. When used
to locate a known cellular device, a cell site simulator initially receives the unique identifying
number from multiple devices in the vicinity of the simulator. Id. Once the cell site simulator
identifies the specific cellular device for which it is looking, it will obtain the signaling
information relating only to that particular phone. Id. When used to identify an unknown
device, the cell site simulator obtains signaling information from non-target devices in the
target’s vicinity for the limited purpose of distinguishing the target device. Id.
By transmitting as a cell tower, cell site simulators acquire the identifying information
from cellular devices. Hansen Decl. ¶ 7. This identifying information is limited, however. Id.
Cell site simulators provide only the relative signal strength and general direction of a subject

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 cellular telephone; they do not function as a GPS locator, as they do not obtain or download any
location information from the device or its applications. Id. Moreover, cell site simulators used
by federal, state, and local law enforcement agencies must be configured as pen registers, and
may not be used to collect the contents of any communication, in accordance with 18 U.S.C.
§ 3127(3). Hansen Decl. ¶ 7. This includes any data contained on the phone itself: the cell site
simulator does not capture emails, texts, contact lists, images, or other data from the phone, nor
does it, as configured, provide subscriber account information (such as an account holder’s
name, address, or telephone number). Id.
Cell site simulator technology provides valuable assistance in support of law enforcement
and public safety matters. Hansen Decl. ¶ 3. Whether deployed as part of a fugitive
apprehension effort, a complex narcotics investigation, or to locate and rescue a kidnapped child,
cell site simulators fulfill critical operational needs. Id. Cell site simulator technology is also an
important tool in the federal government’s effort to protect and defend the United States against
terrorist and other threats to our national security. Id.
II.

LIMITS ON ACCESS TO CELL SITE SIMULATOR TECHNOLOGY
Federal law prohibits the use of any radio transmission equipment, which includes cell

site simulator equipment, except as authorized by the Federal Communications Commission
(“FCC”). See 47 U.S.C. §§ 301, 302a; see also 18 U.S.C. § 2512. Since 2010, the FCC has
authorized manufacturers to sell cell site simulator equipment to state and local law enforcement
agencies on two specific conditions: “(1) The making and sale of these devices shall be limited
to federal, state, and local public safety and law enforcement officials only; and (2) state and
local law enforcement agencies must [in] advance coordinate with the FBI the acquisition and
use of the equipment authorized under this authorization.” Hansen Decl. ¶¶ 9-10 & Exh. A.

4

 This advance coordination has been accomplished through and documented by a nondisclosure agreement (“NDA”) executed between the state or local law enforcement agency and
the FBI. Hansen Decl. ¶ 10. The DSP signed such an NDA with the FBI in 2012. Id. ¶ 12 &
Exh. B (FBI-DSP Non-Disclosure Agreement). Only upon execution of the NDA may a state or
local agency purchase or otherwise acquire, use, or provide training about operating cell site
simulator equipment. Id. ¶ 10. When a state or local law enforcement agency contacts one of
the two authorized manufacturers about purchasing cell site simulator equipment, the
manufacturer notifies the FBI about the agency’s interest. Id. The FBI then contacts the agency
to begin the coordination process, including the NDA. Id. Once the NDA is completed, the FBI
notifies the manufacturer that the coordination has taken place. Id.
Through the NDAs, state and local law enforcement agencies stipulate that they will not
disclose information about the technology and equipment and that they will notify the FBI upon
receipt of any request for such information to provide the federal government the opportunity to
protect the important federal equities at stake. Hansen Decl. ¶ 11. The NDA signed by DSP
contained such a provision. Id. ¶¶ 12, 13. The NDA provides that the DSP “will not distribute,
disseminate, or otherwise disclose any information concerning the wireless collection
equipment/technology or any software, operating manuals, or related technical documentation
(including its technical/engineering description(s) and capabilities) to the public, including to any
non-law enforcement individuals or agencies.” Id. ¶ 13 & Exh. B. In addition, the agreement
provides that in the event that the DSP receives a request for such information pursuant to
federal, state, or local law or in a court or administrative proceeding, it will immediately contact
the FBI in order to allow sufficient time for the FBI to seek to prevent disclosure through
appropriate channels. Hansen Decl., Exh. B ¶¶ 7, 11.

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 III.

RUDENBERG’S DELAWARE FOIA REQUEST
On May 15, 2015, Rudenberg submitted a request to the Delaware State Police pursuant

to the Delaware FOIA, Del. Code tit. 29, §§ 10001-10007, for records related to the acquisition
and use of cell site simulators by the DSP. See Appellant’s Opening Br. (“Rudenberg Br.”) 5 &
Exh. A thereto. The request contains nine subparts, seeking, inter alia, records relating to: (1)
the DSP’s acquisition of cell site simulators, including invoices, purchase orders, and similar
documents; (2) any agreements between the DSP and other law enforcement agencies to share
the use of cell site simulators; (3) any pertinent non-disclosure agreements; (4) DSP policies and
guidelines governing the use of cell site simulators; (5)-(6) any agreements with wireless service
providers or communications, licenses, or agreements with the FCC or the Delaware Public
Service Commission; and (7)-(9) the number of investigations in which cell site simulators have
been used by the DSP, a list of cases in which cell site simulators were used as part of the
underlying investigation, and any applications for warrants or court orders authorizing the use of
cell site simulators. Id.; see also Appellee’s Opening Br. (“DSP Br.”) 1-3.
On June 5, 2015, the Delaware State Police responded to the request by stating that the
records could not be divulged pursuant to the FBI-DSP NDA. DSP Br. 3. On June 17, 2015,
Rudenberg filed a petition for review of this response with the Chief Deputy Attorney General,
pursuant to section 10005(b) of the Delaware FOIA, Del. Code tit. 29, § 10005(b). DSP Br. 3.
In the meantime, the DSP brought Rudenberg’s request and this suit to the FBI’s
attention in compliance with the NDA it had previously signed with the FBI. Hansen Decl. ¶ 19.
The FBI began working with the DSP to identify information that can be released without risking
harm to law enforcement and national security interests. Id. Among the records that DSP had
identified as responsive to Rudenberg’s request are ten pages of purchase orders and invoices

6

 related to DSP’s acquisition of CSS systems and training. DSP Br. 15-16. After consultation
with the FBI, DSP redacted from these pages the makes and model numbers of the cell site
simulator equipment and the component parts and software necessary to configure CSS systems.
Hansen Decl. ¶ 19. The FBI has assessed that disclosure of this information to the public would
pose significant risks to effective law enforcement, and ultimately to the safety of the public and
the national security of the United States. Id. ¶ 20.
The Chief Deputy Attorney General (“CDAG”) issued her decision in Rudenberg’s
appeal on December 29, 2015. DSP Br. 4. The CDAG found that the non-disclosure agreement
between the DSP and the FBI was subject to disclosure and ordered DSP to release that
agreement (which DSP did). Id. She also directed DSP to release the redacted purchase order
records (discussed in the previous paragraph), which DSP also did. Id. at 4-5.
On February 26, 2016, Rudenberg appealed the Chief Deputy’s decision to this Court,
pursuant to § 10005(b) of the Delaware FOIA. DSP Br. 5. In this appeal, Rudenberg challenges,
inter alia, the redactions made to the purchase order records, arguing that he is entitled to
information concerning the specific model names. Rudenberg Br. 22-23.
ARGUMENT
THE REDACTED INFORMATION IS EXEMPT FROM DISCLOSURE UNDER
DELAWARE FOIA SECTION 10002(l)(6)
Section 10002(l)(6) of the Delaware FOIA defines a “public record” subject to release as
excluding “[a]ny records specifically exempted from public disclosure by statute or common
law.” Del. Code, tit. 29, § 10002(l)(6); see generally Guy v. Judicial Nominating Comm’n, 659
A.2d 777, 783 (Del. Super. 1995) (adopting a broad meaning of word “statute” in specifically
holding that “the word ‘statute' within the meaning of this exemption under the Act is
sufficiently inclusive to embrace provisions of the State Constitution”). As discussed further
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 below, the information at issue here, specifically, the makes and model numbers of cell site
simulators purchased by DSP, and information regarding component parts and software, is
protected both under a federal statute – the federal FOIA – and under federal common law – the
law enforcement sensitive privilege. Accordingly, this information is exempt from disclosure
under Delaware’s FOIA and was properly redacted from the purchase orders.
A.

The Redacted Information is Specifically Exempted From Disclosure by the
Federal FOIA, 5 U.S.C. § 552

Under the federal FOIA, records or information compiled for law enforcement purposes
are not subject to public disclosure when such disclosure would reveal “techniques and
procedures for law enforcement investigations or prosecutions, or would [reveal] guidelines for
law enforcement investigations or prosecutions if such disclosure could reasonably be expected
to risk circumvention of the law.” 5 U.S.C. § 552(b)(7)(E). Pursuant to this exemption, federal
courts have protected non-public details about a wide variety of commonly known law
enforcement techniques and procedures. See The United States Department of Justice Guide to
the Freedom of Information Act, Exemption 7(E) at p. 6-9, https://www.justice.gov/oip/dojguide-freedom-information-act-0 (compiling cases standing for the proposition that non-public
details about publicly-known techniques and procedures, such as surveillance, are covered by
Exemption 7(E) because disclosure of such could reduce or nullify the effectiveness of the
techniques and procedures); see ,e.g., Kurdyukov v. U.S. Coast Guard, 657 F. Supp. 2d 248, 257
(D.D.C. 2009) (“An agency may withhold information from disclosure where, as here, it would
provide insight into its investigatory or procedural techniques.”); Fisher v. U.S. Dep’t of Justice,
772 F. Supp. 7, 12 (D.D.C. 1991) (upholding FBI’s decision to withhold information about law
enforcement techniques where disclosure “could alert subjects in drug investigations about
techniques used to aid the FBI”), aff’d, 968 F.2d 92 (D.C. Cir. 1992).
8

 As described above, cell site simulators are a key tool in the investigation, interdiction,
and suppression of criminal and terrorist activity. Hence, information about this technology falls
within the purview of Exemption 7(E). Such information is protected because, as explained by
William Hansen, current Chief of the Tracking Technology Unit in FBI’s Operational
Technology Division, disclosure of even minor details about cell site simulators can reasonably
be expected to provide adversaries – criminals and terrorists alike – with the ability to develop
defensive technology, modify their behaviors, and otherwise take countermeasures designed to
circumvent the law. Hansen Decl. ¶ 22. Disclosure of the information at issue here (make and
model information and information regarding software updates, component parts, and training
manuals from purchase orders) would reveal the relative capabilities – and corresponding
limitations – of DSP to electronically surveil and locate criminals and terrorists, and
rescue/recover crime victims because it would reveal the specific resources available to the
police department (as well as those not available to it). Id. ¶ 23.a. Disclosure of this information
would not only implicate the equities and safety of the community in Delaware. Id. Combined
with other information that may be available to criminals and terrorists concerning other
jurisdictions, disclosure of make and model information used by the DSP would permit the
development and honing of “heat maps” identifying the areas in the country where particular
technology and resources are utilized by law enforcement and where they are not – i.e., those
areas where criminals and terrorists can operate without fear of detection by cell site simulator
technology and those areas where they need to modify their behaviors (or that they need to
avoid) because the likelihood that law enforcement will be able to locate them is greater. Id.
Thus, the information at issue in this category not only reflects on the resources that DSP can
bring to bear in its cases, but also adds critical information to the fund already available for

9

 criminals and terrorists to use in order to strategically navigate and thwart law enforcement on a
broad scale. Id.
Furthermore, disclosure of listings of particular components necessary to configure
particular systems would also reveal tradecraft information about platforms and modes of
operation of CSS equipment. Hansen Decl. ¶ 23.b. Because this information would reveal not
only the platforms and modes on which DSP operates its gear specifically, but also the tradecraft
capabilities of others using the gear including federal law enforcement agencies, disclosure of
this information would permit criminals and terrorists across the country to devise strategies to
avoid the reach of the gear, develop technological countermeasures, and otherwise thwart the
technology in order to circumvent local, state, and federal law. Id.
Accordingly, the information at issue here would be exempt from release under FOIA
Exemption 7(E). Rudenberg asserts that the information he sought in his request has “routinely”
been ordered to be disclosed under the federal FOIA, citing American Civil Liberties Union v.
United States Department of Justice, No. 13-cv-03127-MEJ, 2015 WL 3793496 (N.D. Cal. June
17, 2015), and American Civil Liberties Union v. United States Department of Justice, 655 F.3d
1, 19 (D.C. Cir. 2011). Rudenberg Br. 5. He is wrong – the type of information about cell site
simulators that the FBI seeks to protect here has not been ordered disclosed in federal FOIA
cases, let alone on a routine basis. See Rigmaiden v. Fed. Bureau of Investigation, No. 2:12-cv01605-DLR-BSB (D. Ariz.) (orders dated Aug. 31, 2015 & Dec. 14, 2015) (attached as Exhibits
A and B to Federighi Decl.). First, in the District of Columbia case cited by Rudenberg, the
court rejected the government’s assertion of Exemptions 6 and 7(C) and directed the government
to produce “docket information from criminal cases in which the government prosecuted
individuals after judges granted applications for cell phone location data without determining

10

 probable cause, and in which those individuals were ultimately convicted or entered public guilty
pleas.” ACLU v. U.S. DOJ, 655 F.3d at 19-20 (emphasis added). The holding of the case thus
did not concern technical or make/model information about cell site simulators, or even the
application of Exemption 7(E).
In the California case cited by Rudenberg, at issue ultimately were legal templates for
applications and proposed orders related to cell site simulators; legal guidance memoranda
regarding use of cell site simulators; an excerpt from the USA Book; and a sealed search
warrant, application, and affidavit. ACLU v. DOJ, 2015 WL 3793496, at *2. The district court
did conclude that DOJ’s assertion of Exemption 7(E) to protect documents drafted by legal
advisors and a reference document prepared to assist prosecutors and law enforcement agents
was insufficient. Id. at *11. However, the information at issue was not the same as the type of
technical information that the FBI seeks to protect here. In any event, to the extent that there is
some similarity between the information in the two cases, this single decision finding that DOJ
had not met its burden to protect such information under Exemption 7(E) does not demonstrate
that courts “routinely” order disclosure under the federal FOIA of the types of information the
FBI seeks to protect. See also Hodai, 365 P.3d at 964-66 (applying balancing test to find that the
Tucson Police Department properly withheld cell site simulator training materials in response to
a request under the Arizona Public Records Act, concluding that statement of FBI agent that
“knowledge of how the equipment works ‘could easily lead to the development and employment
of countermeasures’ . . . is not merely a possible harm based on a hypothetical situation, but one
rooted in experience”).
In sum, the information redacted from the purchase orders is exempt from disclosure
pursuant to Exemption 7(E) of the federal FOIA. As a result, the information is therefore exempt

11

 from disclosure under § 10002(l)(6) of the Delaware FOIA as information “specifically
exempted from public disclosure by statute.”
B.

The Redacted Information is Specifically Exempted From Disclosure by the
Common Law Under the Law Enforcement Privilege

In addition to falling with the federal FOIA exemption 7(E), information about cell site
simulators is confidential, privileged information that is protected from disclosure in criminal
discovery under the “law enforcement sensitive” privilege. Accordingly, it falls within the scope
of § 10002(l)(6) for this reason as well.
The “law enforcement sensitive” privilege applies in criminal cases to protect
information where disclosure of that information would allow criminal defendants and others to
ascertain law enforcement’s capabilities and limitations in this area, and thus to develop
countermeasures. See United States v. Rigmaiden, 844 F. Supp. 2d 982, 992 (D. Ariz. 2012)
(federal criminal prosecution); United States v. Garey, No. 5:03-CR-83, 2004 WL 2663023
(M.D. Ga. Nov. 15. 2004) (same). The “law enforcement privilege” balances the defendant’s
need for the information against the public interest in confidentiality. Rigmaiden, 844 F. Supp.
2d at 988-89. The privilege applies to the information at issue here because, as the FBI Program
Manager avers, public knowledge of this information could jeopardize the effectiveness of the
use of cell site simulators as an investigative tool. Hansen Decl. ¶¶ 20-23. Although some
general information about cell site simulators and their operation is publicly available, the
specific capabilities, settings, limitations, tradecraft, and other types of information withheld here
have not been authoritatively disclosed or confirmed by the FBI. Id. ¶ 25. As explained above,
disclosure of this information would therefore add critical information to the fund already
available for criminals and terrorists to use in order to strategically navigate and thwart law
enforcement on a broad scale. Id.
12

 The federal courts have found that information regarding cell site simulators is protected
by this “law enforcement sensitive” privilege. In Rigmaiden, based on the testimony of an FBI
Supervisory Special Agent, the court found that the privilege applied to “the precise equipment
used by the FBI and the precise manner in which it was used,” including information such as the
manufacturer model information, instructions, user manuals and other technical and operational
information. 844 F. Supp. 2d at 993-94. The court concluded that disclosure of this information
“would enable adversaries of law enforcement to defeat electronic surveillance operations and to
avoid detection by such surveillance” and therefore “would compromise the ability of the FBI
and other law enforcement agencies to combat crime.” Id. at 994; see also id. at 1002
(“Disclosure of the specific equipment used by the government . . . would hamper future law
enforcement efforts . . . .”), 1004. Accord United States v. Garey, No. 5:03-CR-83, 2004 WL
2663023, *4 (M.D. Ga. Nov. 15, 2004) (upholding the assertion of investigative privilege with
respect to information regarding the cell site simulator equipment employed during a criminal
investigation).
At least one state court has found similar material protected by a similar state-law
privilege. See People v. Michaels, No. 5-140709-7 (Cal. Super. Ct., County of Contra Costa)
(orders dated Nov. 4, 2015 & Dec. 3, 2015) (attached as Exhs. C & D to Federighi Decl.) (state
criminal prosecution). In Michaels, criminal defendants sought pretrial discovery relating to the
use of cell site simulators, and the State opposed the discovery request asserting that the
information was protected by the official government privilege under California Evidence Code
1040. California’s “official information” privilege protects non-public, confidential information
from disclosure when disclosure is “against the public interest.” Cal. Evid. Code § 1040(b)(2).
Based on testimony presented by an FBI Supervisory Special Agent, the Superior Court held that

13

 the following information was protected: “[t]he make, model, manufacturer, technical
specifications, and capabilities of the particular cell site simulator device used in this
investigation; the specific techniques employed in operating the cell site simulator in this
investigation; and the names and identities of the individual agents who operated the cell site
simulator in this investigation.” Order dated Nov. 4, 2015, at 8. As the court explained,
“disclosure of this information would enable those suspected of crimes and fugitives from justice
to avoid or defeat the efficacy of the cell site simulator” and thus “compromise the ability of law
enforcement officers to investigate, solve, prosecute, and prevent crimes.” Id. at 8-9. Thus,
“disclosure of the information listed above would be against the public interest because there is a
necessity for preserving the confidentiality of this information that outweighs the necessity for
disclosure to the Defendants in the interest of justice.” Id. at 8.
In sum, the information that DSP protected here at the FBI’s request falls within the
categories of sensitive law enforcement information that have been found privileged in federal
and state courts, and thus that have been exempted from disclosure. Accordingly, this
information is “specifically exempted from public disclosure by . . . common law” and exempt
from disclosure under § 10002(l)(6) of the Delaware FOIA for this reason as well.

14

 CONCLUSION
For all the foregoing reasons, the United States respectfully requests that the Court find
that the DSP properly withheld the information described above and deny Rudenberg’s appeal.
Respectfully submitted,
BENJAMIN C. MIZER
Principal Deputy Assistant Attorney General
MARCIA BERMAN
Assistant Branch Director
s/Carol Federighi
CAROL FEDERIGHI
Senior Trial Counsel
United States Department of Justice
Civil Division, Federal Programs Branch
20 Massachusetts Avenue N.W. Room 7122
Washington, D.C. 20530
Tel.: (202) 514-1903
E-mail: carol.federighi@usdoj.gov

Dated: September 27, 2016

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