Marcantoni v. Sodd et al

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF MARYLAND
ANTHONY MARCANTONI, 	*
*
Plaintiff, 	*
* 	Civil Action No. 8:18-cv-00134-PX
v. 	*
*
STEVEN SODD, 	et al., 	*
*
Defendants. 	*
***
MEMORANDUM OPINION
Pending in this civil rights action are cross-motions for summary judgment filed by
Plaintiff 	Anthony 	Marcantoni 	(“Marcantoni”) 	and 	Defendants 	Steven 	Sodd 	(“Sodd”) 	and
Christopher Toland (“Toland”) (collectively, “Defendants”), two detectives with the Baltimore
County Police Department (“BCPD”). 	ECF Nos. 115 & 117. 	No hearing is necessary. 	D. Md.
Loc. R. 105.6. 	For the following reasons, Defendants’ motion for summary judgment is
GRANTED, and Marcantoni’s motion is DENIED as moot.
I. 	Background
Except where otherwise noted, the following facts are undisputed. This case arises out of
BCPD’s investigation into a marijuana trafficking scheme allegedly spearheaded by Jacob
Jeremiah Harryman (“Harryman”). 	See 	ECF No. 115-21 at 2. 	Detectives Sodd and Toland led
the investigation, which included working with confidential informants, performing surveillance,
and conducting controlled buys. ECF Nos. 115-6 at 7–8, 115-10 at 2, & 115-17 at 2.
By October of 2010, the detectives had identified Marcantoni as a significant member of
Harryman’s network. 	Id. 	at 3; ECF No. 115-21 at 2. 	The detectives also determined that
Marcantoni was using “multiple cellular telephones to conduct [the] criminal enterprise.” 	Id.
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Based on that information, the detectives planned to seek a court order to wiretap Marcantoni’s
phones. ECF No. 115-6 at 7. But first they needed to identify the telephone numbers associated
with each device that Marcantoni was using. 	See 	ECF No. 115-21 at 2. The detectives’ specific
efforts to obtain these phone numbers lie at the heart of this case.
The participants in the narcotics ring used several “burner phones” to transact business.
ECF Nos. 115-6 at 93 & 115-21 at 2. 	Marcantoni was suspected of simultaneously employing up
to nine burner phones, which customarily have no associated subscriber information. 	ECF No.
115-6 at 16, 108.
After receiving departmental permission, Sodd applied for a court order that allowed the
detectives to use a cell-site simulator (“CSS”), sometimes referenced by its brand name, DRT, to
identify the phones Marcantoni was using.1 	ECF No. 115-21 at 2; 	see 	ECF No. 115-5 at 10–11,
19. A CSS is a device that emits signals that mimic those from a cell phone tower. 	Id. 	at 10–11.
“When powered on, a cell phone . . . automatically announces its presence to” nearby cell towers
“via a radio signal over a control channel” that, in turn, connects with a cellular network. 	United
States v. Temple, No. S1–4:15 CR 230–1 JAR (JMB), 2017 WL 7798109, at *27 (E.D. Mo. Oct.
6, 2017) (quoting 	United States v. Bermudez, No. IP 05-43-CR-B/F, 2006 WL 3197181, at *6
(S.D. Ind. June 30, 2006)). 	When a cell phone connects to a network, it reveals an embedded
unique identifier. 	See id. 	at *27–28. 	Depending upon the cellular network and the device, this
identifier might take several forms, including an Electronic Serial Number (“ESN”), Mobile
Electronic Identity Number (“MEIN”), a Mobile Identification Number (“MIN”), an International
Mobile Subscriber Identifier (“IMSI”), or an International Mobile Station Equipment Identity
(“IMEI”). 	Id.; ECF No. 115-6 at 105.
1 	Between 2008 and 2010, the BCPD began purchasing CSS technology, including DRT and “StingRay II.” 	ECF
Nos. 115-3, 115-4, & 115-5 at 17.
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Law enforcement can use a CSS to draw cell phones to the CSS device instead of proximate
cell towers. ECF No. 115-13 at 3; 	see also 	ECF No. 115-5 at 21. Once the cell phones connect to
the CSS, the CSS records the unique identifiers for the phones as well as their geographic locations.
Id. 	at 14–15. 	While connected to the CSS, the cell phones cannot also connect to a cellular tower,
rendering the cell phones inoperable. ECF No. 115-9 at 103.
In Marcantoni’s case, Defendants used the CSS to obtain the unique identifier associated
with his cell phone so that they could next link the identifier to the phone number associated with
his device. ECF Nos. 115-6 at 19 & 115-21 at 2. On October 14, 2010, Sodd applied to the Circuit
Court of Baltimore County for an order to use the CSS to investigate Marcantoni. ECF No 115-
22. In the application, Sodd attested that Marcantoni was under investigation for drug distribution,
and in connection with his drug activity, was “using one or more unidentified wireless telephones.”
Id. 	at 2. 	The application further attested that using “a pen register and trap and trace device” at
locations in Baltimore County where Marcantoni lives or frequents would allow law enforcement
to capture the phone’s unique identifying numbers, which is what they needed to ascertain the
cellphone number associated with Marcantoni’s phone. 	Id. 	at 2–3. 	The application, in turn,
requested
[A]n order authorizing the installation and use of a pen register and trap and trace
device 	for a period of sixty (60) days to detect radio signals emitted from wireless
cellular telephones in the vicinity of [Marcantoni] that identify the telephones (e.g.,
by transmitting the telephone’s serial number and phone number) to the network
for authentication. 	By determining the identifying registration data at various
locations in which the Subject Telephone is reasonably believed to be operating,
the telephone number corresponding to the Subject Telephone can be identified.
Id. 	at 3. The application also informed the judge that:
Data 	transmitted 	during 	autonomous 	registration 	is 	not 	dialed 	or 	otherwise
controlled by the telephone user. It is an autonomous transmission that occurs when
the phone is turned on and periodically thereafter, regardless of whether a call is
being made, and in fact, is clearly separate from the establishment or maintenance
of a call.
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Id.
The application, however, failed to tell the court that unlike a traditional “pen register or
trap and trace device,” the CSS would capture more than just incoming or outgoing phone
numbers. 	Id. 	at 2.2
The Circuit Court granted the application that same day by written order. ECF No. 115-
23. The next day, on October 15, 2010, seven officers set up visual surveillance at Marcantoni’s
residence and place of business. 	See 	ECF No. 115-27 at 2; 	see also 	ECF No. 115-6 at 19 (Sodd
describing the general practice of surveilling a suspect for the purpose of using CSS). 	Officers
observed Marcantoni leaving his home, getting into his truck, and driving to his place of business,
where unknown individuals waited to enter. ECF No. 115-27 at 2. Marcantoni, who was carrying
a backpack, then unlocked the doors to his business and went inside. 	Id.
During the surveillance, officers deployed the CSS first when they spotted Marcantoni at
his home. 	Id.; ECF No. 115-24 at 25. Officers next followed Marcantoni to his job and used the
CSS again. ECF No. 115-27 at 2; 	see 	ECF No. 115-26 at 3. 	At each location, the CSS recorded
2A pen register is “a device or process which records or decodes dialing, routing, addressing, or signaling
information transmitted by an instrument or facility from which a wire or electronic communication is transmitted,”
without recording the contents of such information. 18 U.S.C. § 3127(3); Md. Code Ann., Cts. & Jud. Proc., § 10-
4B-01(c)(1). A trap-and-trace device “captures the incoming electronic or other impulses which identify the
originating number or other dialing, routing, addressing, and signaling information reasonably likely to identify the
source of a wire or electronic communication.” 18 U.S.C. § 3127(4); Md. Code Ann., Cts. & Jud. Proc., § 10-4B-
01(d)(1). Accordingly, because pen registers or trap-and-trace devices capture no more than the call numbers placed
to or from a known telephone number, they do not constitute a search requiring a warrant. 	See Smith v. Maryland,
442 U.S. 735, 745–46 (1979). Unlike the probable cause standard necessary to obtain a warrant, Maryland Rule 10-
4B-04 regarding pen register and trap-and-trace orders requires that the issuing court find “the information likely to
be obtained by the installation and use is relevant to an ongoing criminal investigation.” Md. Code Ann., Cts. &
Jud. Proc., § 10-4B-04(a)(1). This Court doubts that the order Detective Sodd obtained amounts to a search warrant,
principally because the Circuit Court made no probable cause determination. 	See State v. Andrews, 	277 Md. App.
350, 403–06 (Md. Ct. Spec. App. 2016) (holding that “the pen register statute . . . is limited by its terms and is not
intended to apply to other, newer technologies,” 	id. 	at 406, such as CSS). Further, because the Court concludes that
the officers are qualifiedly immune even when construing the CSS use as a warrantless search, 	see infra 	at 12–14, 	it
need not resolve this question. 	Cf. Andrews v. Balt. City Police Dep’t, 2026 WL 2872021, at *12 (4th Cir. 2026)
(Quattlebaum J., concurring in part and in the judgment) (reasoning that officers enjoyed qualified immunity
because the application for CSS amounts to a warrant, thereby obviating the need to squarely reach whether the use
of CSS technology constitutes a search).
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the unique identifying numbers of all cell phones in its range. 	See 	ECF No. 115-26. The BCPD’s
Intelligence Unit next cross-referenced the unique identifiers obtained by the CSS from both
locations to isolate the common identifier, and next subpoenaed from the relevant cell phone
carrier the cell phone number associated with that common identifier. 	See 	ECF Nos. 115-5 at 15–
16, 115-6 at 18, 115-7 at 19, & 115-26 at 5–6, 8; 	see also 	ECF No. 115-9 at 43–46. 	Once the
Defendants obtained this information, they identified Marcantoni’s cell phone number from
previous wiretaps and eventually sought and obtained authorized wiretaps for that number. ECF
No. 115-6 at 99–103, 106.
Thereafter, Marcantoni was federally charged with conspiracy to distribute and possess
with intent to distribute 1,000 kilograms or more of marijuana. 	See United States v. Nicka,
Criminal No. DKC-10-777-15 (D. Md.). 	During the criminal case, prosecutors did not disclose
that the government used a CSS to identify Marcantoni’s phone number. 	See 	ECF No. 115-1 at 3.
Consequently, the myriad challenges to evidence obtained via wiretap did not address the issues
raised in this case.
After suppression was denied on other grounds, Marcantoni ultimately pleaded guilty and
was sentenced to 121 months imprisonment. 	Id. 	Marcantoni appealed his conviction and sentence.
Id. 	While his criminal appeal was pending, he filed this civil suit pursuant to 42 U.S.C. § 1983
against Sodd and Toland, alleging that their warrantless use of the CSS had violated his Fourth
Amendment right to be free from unreasonable searches and seizures. 	ECF No. 1. 	The Court
dismissed the Complaint, reasoning that it was barred under 	Heck v. Humphrey, 512 U.S. 477
(1994), because the criminal conviction had not been vacated or otherwise invalidated. ECF No.
3 at 2. The Fourth Circuit reversed, concluding that the Complaint was not barred because “the
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claimed Fourth Amendment violation does not necessarily imply the invalidity of Marcantoni’s
criminal conviction.” ECF No. 14-1 at 3.
The Court next entertained and denied another round of challenges to the claim. ECF No.
90 at 1. 	Guided by the Fourth Circuit in 	Andrews v. Baltimore City Police Department, 8 F.4th
234 (4th Cir. 2020), the Court denied dismissal to ensure full factual development on the CSS’s
“degree of intrusion onto constitutionally protected areas.” ECF No. 90 at 3 (quoting 	Andrews, 8
F.4th at 236). The Court also appointed counsel to represent Marcantoni in further proceedings.
ECF No. 92. 	Following the close of discovery, the parties filed cross-motions for summary
judgment. 	See 	ECF Nos. 115 & 117. The matter is now ripe for resolution.
II. 	Standard of Review
Summary judgment is appropriate when the Court, viewing the evidence in the light most
favorable to the non-moving party, finds no genuinely disputed issue of material fact, entitling the
movant to judgment as a matter of law. Fed. R. Civ. P. 56(a); 	Celotex Corp. v. Catrett, 477 U.S.
317, 322 (1986); 	Emmett v. Johnson, 532 F.3d 291, 297 (4th Cir. 2008). 	“A party opposing a
properly supported motion for summary judgment ‘may not rest upon the mere allegations or
denials of [his] pleadings,’ but rather must ‘set forth specific facts showing that there is a genuine
issue for trial.’” 	Bouchat v. Balt. Ravens Football Club, Inc., 346 F.3d 514, 522 (4th Cir. 2003)
(alteration in original) (quoting former Fed. R. Civ. P. 56(e)). “A mere scintilla of proof . . . will
not suffice to prevent summary judgment.” 	Peters v. Jenney, 327 F.3d 307, 314 (4th Cir. 2003).
Importantly, “a court should not grant summary judgment ‘unless the entire record shows
a right to judgment with such clarity as to leave no room for controversy and establishes
affirmatively that the adverse party cannot prevail under any circumstances.’” 	Campbell v. Hewitt,
Coleman & Assocs., Inc., 21 F.3d 52, 55 (4th Cir. 1994) (quoting 	Phoenix Sav. & Loan, Inc. v.
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Aetna Casualty & Sur. Co., 381 F.2d 245, 249 (4th Cir. 1967)). Where the party bearing the burden
of proving a claim or defense “fails to make a showing sufficient to establish the existence of an
element essential to that party’s case, and on which that party will bear the burden of proof at trial,”
summary judgment against that party is likewise warranted. 	Celotex, 477 U.S. at 322. On cross-
motions for summary judgment, “a court must ‘evaluate each party’s motion on its own merits,
taking care [in each instance] to draw all reasonable inferences against the party whose motion is
under consideration.’” 	Snyder ex rel. Snyder v. Montgomery Cnty. Pub. Schs., Civil Action No.
DKC 2008-1757, 2009 WL 3246579, at *5 (D. Md. Sep. 29, 2009) (quoting 	Bd. of Educ. of
Frederick Cnty. v. I.S. ex rel. Summers, 325 F. Supp. 2d 565, 578 (D. Md. 2004)).
III. 	Analysis
Marcantoni argues that Defendants violated his Fourth Amendment right to freedom from
unreasonable searches and seizures. 	He asserts that he maintained a reasonable expectation of
privacy in the unique identifier captured by the CSS, and the application for use of the CSS
bypassed the more demanding probable cause standard necessary to issue a search warrant. ECF
Nos. 115-1 at 17–18 & 115-22 at 2. 	Defendants respond that using a CSS to extract the unique
identifier implicates no reasonable expectation of privacy protected under the Fourth Amendment,
and so, does not amount to a search. ECF No. 117-1 at 6.3 	Alternatively, Defendants argue that
even if it was a search, they enjoy qualified immunity from suit. 	Id. 	at 20–24.
3 	Defendants also argue that because they did not personally deploy the CSS, they cannot be held liable for any
constitutional violations. ECF No. 117 at 20. The Court rejects this argument as reductionist. Sodd and Toland by
their own admission were the “lead detectives” investigating Marcantoni’s place in the Harryman “drug
organization,” meeting weekly with Circuit judges to obtain seriatim wiretaps, pen registers, and other means of
investigation. ECF No. 115-10 (Sodd Affidavit). Sodd was the affiant on the application for the CSS used to obtain
Marcantoni’s phone information, and Toland testified to his personal involvement in deciding to use the CSS. 	Id.;
ECF No. 115-7 at 23–24. Accordingly, a reasonable juror could conclude that the Defendants decided to use the
CSS even if another officer technically operated the device.
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The merits of Marcantoni’s claim and the defense of qualified immunity both depend on
whether Defendants violated Marcantoni’s Fourth Amendment right to be free from warrantless
searches. Qualified immunity protects officers from 	civil suits arising from their alleged
constitutional violations if “their conduct does not violate clearly established statutory or
constitutional rights of which a reasonable person would have known.” 	Harlow v. Fitzgerald, 457
U.S. 800, 818 (1982); 	accord Pritchett v. Alford, 973 F.2d 307, 312 (4th Cir. 1992). 	Where the
plaintiff has demonstrated that the challenged police conduct violates a constitutional right, the
defendant officer may still be immune from suit if the “right at issue” was not “clearly established
at the time of defendant’s alleged misconduct.” 	Id. 	at 232 (quoting 	Saucier v. Katz, 533 U.S. 194,
201 (2001)). Although the Court may consider these twin prongs in the order which best suits “the
circumstances in the particular case at hand,” 	id. 	at 236, it is preferable to consider first whether
the officer’s conduct violated the plaintiff’s particular constitutional right, because such a
determination advances the discourse as to whether the right is clearly established, 	id.; 	Saucier,
533 U.S. at 201. 	The parties have engaged in extensive discovery on the challenged police
conduct, and so, the Court ought to further the doctrine, considering that few courts have wrestled
with the constitutional limits of CSS technology to date. The Court thus turns first to whether the
CSS deployment was a search entitled to Fourth Amendment protection.
A. 	The Use of a CSS Constitutes a Search Under the Fourth Amendment
The Fourth Amendment protects individuals “against unreasonable searches and seizures.”
U.S. Const. amend. IV. Its primary purpose “is to safeguard the privacy and security of individuals
against arbitrary invasions by governmental officials.” 	Camara v. Mun. Ct. of City & Cnty. of
S.F., 387 U.S. 523, 528 (1967). 	A constitutionally protected search takes place when law
enforcement “violates a subjective expectation of privacy that society recognizes as reasonable.”
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Kyllo v. United States, 533 U.S.C 27, 33 (2001). A reasonable expectation of privacy must derive
from “a source outside the Fourth Amendment, either by reference to concepts of real or personal
property law or to understandings that are recognized and permitted by society.” 	Minnesota v.
Carter, 525 U.S. 83, 88 (1998) (quoting 	Rakas v. Illinois, 439 U.S. 128, 143 n.12 (1978)).
“[U]nder the reasonable expectation of privacy test, the Fourth Amendment protects against an
unreasonable search of an area in which (1) a person exhibits actual, subjective expectation of
privacy, and (2) the expectation is one that society is prepared to recognize as reasonable.” 	United
States v. Ellis, 270 F. Supp. 3d 1134, 1140 (N.D. Cal. 2017) (citing 	Katz v. United States, 389 U.S.
347, 361 (1967) (Harlan, J., concurring)). 	Thus, absent well-circumscribed exceptions, the
government must obtain a valid search warrant before invading an area in which an individual
maintains a reasonable expectation of privacy. 	See Kentucky v. King, 563 U.S. 452, 459 (2011);
Rakas, 439 U.S. at 143.
When law enforcement obtains evidence “by physically intruding” on “persons, houses,
papers, or effects,” then a search “has undoubtedly occurred.” 	Florida v. Jardines, 569 U.S. 1, 5
(2013) (quoting 	United States v. Jones, 565 U.S. 400, 406 n.3 (2012)). 	But constitutional
protections are not dependent on physical intrusion. 	Indeed, law enforcement’s use of “sense-
enhancing technology” to gather information “that could not otherwise have been obtained without
physical ‘intrusion into a constitutionally protected area’” also amounts to a constitutionally
protected search. 	Kyllo, 533 U.S. at 34 (quoting 	Silverman v. United States, 365 U.S. 505, 512
(1961)); 	see Smith v. Maryland, 442 U.S. 735, 739–41 (1979); 	see also Rakas, 439 U.S. at 143.
As the Supreme Court has instructed, reviewing courts must be mindful that new
technologies may invite a “[s]ubtler and more far-reaching means of invading privacy.” 	Carpenter
v. United States, 585 U.S. 296, 304 (2018) (alteration in original) (quoting 	Olmstead v. United
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States, 277 U.S. 438, 473 (1928) (Brandeis, J., dissenting)). Because cell phones store “a digital
record of nearly every aspect of [people’s] lives,” people enjoy a reasonable expectation of privacy
in such information, and the Fourth Amendment protects against warrantless searches of the same.
Riley v. California, 573 U.S. 373, 395, 401 (2014); see also Carpenter, 585 U.S. at 310 (reasonable
expectation of privacy in cell phone tracking “the whole of [a person’s] physical movements,”);
Chatrie v. United States, 146 S. Ct. 2193, 2206 (2026) (geofencing data invades cell phone
possessor’s reasonable expectation of privacy); 	cf. 	United States v. Lowers, 170 F.4th 134, 147–
48 (4th Cir. 2026) (recognizing a reasonable expectation of privacy in one’s digital files). When
such an expectation exists, any intrusion is a search, no matter how small. 	See Kyllo, 533 U.S. at
38 (citing 	Silverman, 365 U.S. at 512; 	Arizona v. Hicks, 480 U.S. 321 (1987)). “Where the Fourth
Amendment applies, it applies—regardless of ‘the quality or quantity of information’ the
government obtains.” 	Chatrie, 146 S. Ct. at 2210 (quoting 	Kyllo, 533 U.S. at 37).
In a very real sense, therefore, the existence of a constitutional violation comes down to a
basic precept: When it comes to privacy, the government may not do digitally that which it may
not do physically. 	See Chatrie, 146 S. Ct. at 2208; 	Katz, 389 U.S. at 512; 	Jones, 565 U.S. at 429–
30 (Alito, J., concurring in the judgment); 	see also In re Use of a Cell-Site Simulator to Locate a
Cellular Device Associated with One Cellular Telephone Pursuant to Rule 41, 531 F. Supp. 3d 1,
7–8 (D.D.C. 2021). A police officer may not approach a person on the street, open the person’s
cell phone, and search their digital files to obtain the unique identifier belonging to the phone. 	Cf.
Riley, 573 U.S. at 403 (“Our answer to the question of what police must do before searching a cell
phone seized incident to arrest is accordingly simple—get a warrant.”). So too, the officer cannot
use a CSS to grab the identical information. 	Cf. Kyllo, 533 U.S. at 34 (“We think that obtaining
by sense-enhancing technology any information regarding the interior of the home that could not
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otherwise have been obtained without physical ‘intrusion into a constitutionally protected area,’
constitutes a search . . . .” (citation omitted) (quoting 	Silverman, 365 U.S. at 512)). Based on the
undisputed facts, the Detectives’ use of a CSS as enhancing technology to retrieve what is
otherwise embedded in the digital data of the phone amounts to a constitutionally protected search.
Defendants respond that the CSS in this context was no more invasive than the use of a pen
register or a trap-and-trace device, found not entitled to Fourth Amendment protection. 	See 	Smith,
442 U.S. at 745–56; ECF No. 117-1 at 7. However, pen registers and trap-and-trace devices record
nothing beyond the 	outgoing 	phone numbers dialed. 	Smith, 442 U.S. at 742. In 	Smith v. Maryland,
442 U.S. 735 (1979), the Court rejected the notion of a reasonable expectation of privacy in a
dialed phone number because “all telephone users realize that they must ‘convey’ phone numbers
to the telephone company” and further realize that those same numbers are used for billing
purposes. 	Id. 	Although the target of the pen register may have taken steps to keep the conversation
private, “his conduct was not and could not have been calculated to preserve the privacy of the
number he dialed.” 	Id. 	at 743; 	see also 	Katz, 389 U.S. at 351 (“What a person knowingly exposes
to the public . . . is not a subject of Fourth Amendment protection.”).
The same cannot be said for a unique identifier. A cell phone user does not knowingly or
willingly relinquish a unique identifier several times a minute as the cell phone connects to a cell
tower. Accordingly, while use of a CSS may record only a “snapshot” of information as it relates
to the unique identifier and location of its user, 	Andrews v. Balt. City Police Dep’t, No. 18-1953,
2026 WL 2872021, at *8 (4th Cir. Sep. 24, 2026), CSS use nonetheless amounts to a search. This
is so because it is “akin to sense-enhancing technology” which allows law enforcement to extract
information from the cell phone otherwise shielded from public view. 	Id. 	at *9 (citing 	United
States v. Karo, 468 U.S. 705, 714 (1984)). It is, in this regard, no different from the information
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the Court found protected from warrantless searches in 	Riley v. California, 573 U.S. 373, 403
(2014) (contents of cell phone), 	Carpenter v. United States, 585 U.S. 296, 310 (2018) (historical
cell site information), or 	Chatrie v. United States, 146 S. Ct. 2193, 2199 (2026) (cell site
information of short duration).
Moreover, 	the 	information 	itself—the 	cell 	phone’s 	unique 	serial 	number 	that 	tied
Marcantoni’s cell phone to an assigned phone number—is the very kind of information which,
once hidden, cannot be exposed through law enforcement manipulation, absent a warrant or a
recognized exception to the warrant requirement. 	Although Defendants blithely contend that “a
phone’s serial number is hardly more private” than the dialed numbers captured by a pen register,
ECF No. 117-1 at 7, well-worn precedent says otherwise. 	As the Supreme Court made plain in
Arizona v. Hicks, 480 U.S. 321 (1987), a warrantless intrusion to obtain the serial numbers tied to
stereo equipment enjoys equivalent constitutional protection as the information in “letters or
photographs.” 	Id. 	at 325. “It matters not that the search uncovered nothing of any great personal
value to respondent,” namely, “serial numbers.” 	Id. 	“A search is a search, even if it happens to
disclose nothing but the bottom of a turntable.” 	Id. 	Defendants give the Court little reason to part
company with this view. 	Because Marcantoni maintains a reasonable expectation of privacy in
the contents of his cell phone, using a CSS to obtain the phone’s unique identifier amounts to a
search protected under the Fourth Amendment.
The Court next turns to whether the officers enjoy qualified immunity from suit.
B. 	The Constitutionally Protected Right Was Not Clearly Established
The defense of qualified immunity “shields individual law enforcement officers from civil
liability when, in light of clearly established law, they could reasonably have believed that their
actions were lawful.” 	Andrews, 2026 WL 2872021, at *10 (citing 	Henry v. Purnell, 652 F.3d 524,
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531 (4th Cir. 2011)); 	see Atkinson v. Godfrey, 100 F.4th 498, 504 (4th Cir. 2024); 	District of
Columbia v. Wesby, 583 U.S. 48, 62–63 (2018). 	Where a reasonable officer in the defendant’s
shoes would know that his conduct amounts to a Fourth Amendment violation, then qualified
immunity shall lie. 	See Carroll v. Carman, 574 U.S. 13, 16 (2014) (quoting 	Anderson v.
Creighton, 483 U.S. 635, 640 (1987)). For qualified immunity to apply, “the contours of the right
must be sufficiently clear that a reasonable officer would understand that what he is doing violates
that right.” 	Hill v. Crum, 727 F.3d 312, 321 (4th Cir. 2013) (quoting 	Wilson v. Layne, 526 U.S.
603, 615 (1999)). 	The law at the time of the alleged violation must place the issue “beyond
debate.” 	Ashcroft v. al-Kidd, 563 U.S. 731, 741 (2011).
To a reasonable officer in Defendants’ shoes, the right was not clearly established. As the
Fourth Circuit recently explained, CSS technology has been around for decades, but constitutional
challenges to its use have not. 	Andrews, 2026 WL 2872021, at *10. Officers in the Marcantoni
investigation deployed a CSS in 2010. 	Since then, the Supreme Court established in 	Riley 	a
person’s reasonable expectation of privacy in cell phone contents, 73 U.S. at 403, and next
confirmed the privacy right inherent in the “whole of one’s movements” in 	Carpenter. 585 U.S.
at 320. 	Courts, including the Fourth Circuit, more recently applied these principles to law
enforcement’s use of a CSS as a geolocator. 	See Andrews, 2026 WL 2872021, at *1; 	see also
United States v. Gibson, 996 F.3d. 451, 460 (7th Cir. 2021); 	In re Use of a Cell-Site Simulator,
531 F. Supp. 3d at 7; 	Temple, 2017 WL 7798109, at *29 (collecting cases). But as for using CSS
to obtain a cell phone’s unique identifier, only one court has reached the question, seeing it
differently than this Court does. 	See United States v. Woodson, Case No. 4:16CR541AGF(SPM),
2018 WL 7150388, at *9 (E.D. Mo. Nov. 21, 2018) (holding that the use of a CSS to obtain an
identifier from the phone of a suspect whose location is known “does not give rise to the same
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privacy and Fourth Amendment concerns articulated in 	Carpenter”), 	R. & R. adopted, 2019 WL
398453 (E.D. Mo. Jan. 31, 2019). “[T]he ‘contours of the right’” simply were not “so conclusively
drawn as to leave no doubt that the challenged action was unconstitutional.” 	Swanson v. Powers,
937 F.2d 965, 969 (4th Cir. 1991) (quoting 	Anderson, 483 U.S. at 640)). Nor is the right at issue
so fundamentally plain under “existing precedents.” 	Carpenter, 585 U.S. at 306; 	cf. 	Andrews,
2026 WL 2872021, at *7, 10. Accordingly, Defendants are entitled to qualified immunity.
IV. 	Conclusion
For the foregoing reasons, Defendants’ motion for summary judgment is GRANTED on
the defense of qualified immunity, and Marcantoni’s motion for summary judgment is DENIED
as moot. A separate Order follows.
October 15, 2026 	/s/
Date 	PAULA XINIS
United States District Judge
Case 8:18-cv-00134-PX Document 136 Filed 10/15/26 Page 14 of 14