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SJC-12750

             COMMONWEALTH   vs.   JASON J. McCARTHY.



       Barnstable.     October 2, 2019. - April 16, 2020.

  Present (Sitting at Barnstable): Gants, C.J., Lenk, Gaziano,
                Lowy, Budd, Cypher, & Kafker, JJ.


Privacy. Constitutional Law, Privacy, Search and seizure,
     Standing, Admissions and confessions, Voluntariness of
     statement. Search and Seizure, Expectation of privacy,
     Electronic surveillance, Motor vehicle. Practice,
     Criminal, Motion to suppress, Standing, Admissions and
     confessions, Voluntariness of statement. Evidence,
     Admissions and confessions, Voluntariness of statement.



     Indictment found and returned in the Superior Court
Department on August 31, 2017.

     Pretrial motions to suppress evidence were heard by Robert
C. Rufo, J.

     An application for leave to prosecute an interlocutory
appeal was allowed by Kafker, J., in the Supreme Judicial Court
for the county of Suffolk, and the case was reported by him.


     Paul A. Bogosian for the defendant.
     Elizabeth A. Sweeney, Assistant District Attorney, for the
Commonwealth.
     David R. Fox, for Digital Recognition Network, Inc., amicus
curiae, submitted a brief.
                                                                      2


     Matthew Spurlock & David Rassoul Rangaviz, Committee for
Public Counsel Services, Ashley Gorski, of New York, Jennifer
Lynch & Andrew Crocker, of California, Jessie J. Rossman,
Matthew R. Segal, & Nathan Freed Wessler, for American Civil
Liberties Union & others, amici curiae, submitted a brief.


    GAZIANO, J.    While investigating the defendant on suspicion

of drug distribution, police used automatic license plate

readers (ALPRs) on the Bourne and Sagamore bridges to track his

movements.    They accessed historical data, which revealed the

number of times he had crossed the bridges over a three-month

period, and also received real-time alerts, one of which led to

his arrest.   We must determine whether the use of ALPR

technology in this case constituted a search under the Fourth

Amendment to the United States Constitution or under art. 14 of

the Massachusetts Declaration of Rights.

    We conclude that, while the defendant has a

constitutionally protected expectation of privacy in the whole

of his public movements, an interest which potentially could be

implicated by the widespread use of ALPRs, that interest is not

invaded by the limited extent and use of ALPR data in this case.

    1.   Background.     We draw the following from the facts found

by the motion judge, reserving some facts for later discussion.

    a.   ALPR systems.    Automatic license plate readers are

cameras combined with software that allows them to identify and

"read" license plates on passing vehicles.    When an ALPR
                                                                   3


identifies a license plate, it records a photograph of the

plate, the system's interpretation of the license plate number,

and other data, such as the date, time, location, direction of

travel, and travel lane.   In Massachusetts, cameras owned and

maintained by the State police feed this information into a

database maintained by the Executive Office of Public Safety and

Security (EOPSS).1   At some point in 2015, the State police

installed fixed camera readers on both sides of the Sagamore and

Bourne bridges.   While these cameras are not infallible,2 they

essentially create a comprehensive record of vehicles traveling

onto or off of the Cape.

     ALPR systems produce two related types of information:

real-time alerts and historical data.   First, individuals with

user credentials can log onto the ALPR system, enter license

plate numbers onto a "hot list," and choose users to be notified

about any new "hits" for that plate number.   If a camera in the

ALPR system detects a license plate that matches a number on the

hot list, the system sends an electronic mail message or text


     1 According to the amici, private companies also own and
operate automatic license plate reader (ALPR) cameras and share
that data with law enforcement, as do individual homeowners.
Federal and State law enforcement offices, in turn, may share
data with each other.

     2 A testifying expert identified weather conditions, warped
or obscured plates, and particularly bad lighting conditions as
factors that might result in the ALPR failing to read a
particular license plate.
                                                                    4


message to the specified officers.    Alert recipients receive an

image of the plate, along with the date, time, location, and

direction of travel.   Second, users can search by license plate

number for any historical matches stored in the database.      EOPSS

currently has a one-year retention policy for ALPR data.3

     The Barnstable police department has adopted the State

police general order setting out various regulations for the use

of ALPR information.   See State police General Order No. TRF-11

(July 22, 2014) (Order TRF-11).4

     b.   The investigation.   Through surveillance, several

"controlled buys," and information from four confidential

informants, the Barnstable police developed substantial evidence

that a codefendant in this case was distributing heroin from his

residence.   During that surveillance, they observed a black

Hyundai vehicle appear briefly at the codefendant's residence.




     3 Aside from any changes to retention policy or failure to
implement purging according to the policy, electronic mail
messages sent after a real-time alert may be retained longer
than one year, indeed indefinitely, on the recipient's server,
as was the case here.

     4 State police General Order No. TRF-11 (July 22, 2014)
(Order TRF-11) requires, inter alia, that only trained,
specially designated users may access the system; that the "ALPR
System and information shall be . . . [a]ccessed and used only
for official and legitimate law enforcement purpose"; and that
prior to initiating a stop based on an ALPR hit or alert, the
officer must verify visually the alphanumeric characters on the
license plate and verify the status of the plate through one of
various databases.
                                                                    5


After further surveillance, and a tip from a confidential

informant, police observed the defendant driving the same

vehicle, and they began to suspect that he was supplying heroin

to his codefendant.

    On February 1, 2017, Barnstable police added the license

plate number of the black Hyundai to the ALPR hot list, and

specified officers to be notified when it was detected crossing

the Bourne or Sagamore bridges.   On February 8, 2017, several

police officers received an alert that the Hyundai had been

driven over the Sagamore Bridge onto Cape Cod.    Officers

subsequently traveled to the codefendant's house and then

followed him to Shallow Pond Road in Centerville.     At the same

time, another officer found the defendant after he drove onto

the Cape and followed him to Shallow Pond Road.    The officers

watched the defendant and the codefendant meet, but no physical

exchange was observed.   Both vehicles left after approximately

thirty seconds.

    Police also generated a spreadsheet indicating every time

that the Hyundai had passed over the Bourne and Sagamore bridges

between December 1, 2016, and February 12, 2017.    The

spreadsheet contained the dates, times, directions, and specific

lanes that the Hyundai had traveled on the bridges.    The ALPR

spreadsheet showed that the vehicle traveled onto Cape Cod on

eight days in February, twenty-one days in January, and nineteen
                                                                    6


days in December.   On multiple of these days, the defendant made

more than one trip on the same day.   This appeared consistent

with the police theory that the defendant routinely was bringing

heroin onto the Cape for distribution by his codefendant.

     On February 22, 2017, Barnstable police received another

alert that the Hyundai had traveled over the Sagamore Bridge

onto Cape Cod.   Police again followed both the defendant and the

codefendant as they drove to Shallow Pond Road.   The officers

observed a meeting, but did not see an exchange of objects.

Both vehicles departed thirty seconds later.   This time, police

stopped both vehicles on suspicion that a drug transaction had

taken place.

     After stopping the codefendant, police handcuffed him, read

him his Miranda rights, and questioned him at the side of the

road.   He made incriminating statements, and officers found

heroin on his person.   Police also ordered the defendant out of

his vehicle, handcuffed him, and read him his Miranda rights.

The motion judge found that the defendant was under arrest at

the moment that he was ordered out of the Hyundai and

handcuffed.

     At the police station, the defendant waived his Miranda

rights and made various incriminating statements.   Officers also

seized two cellular telephones and United States currency from

the defendant's person.   The defendant's brother brought more
                                                                     7


money to pay the bail for the defendant, but police seized

almost all of the cash on the belief that it was the proceeds of

illegal drug activity.

    The defendant filed motions to suppress the ALPR data and

the fruits of the arrest.    A Superior Court judge held an

evidentiary hearing and then denied the motions.     The defendant

then filed an application for leave to pursue an interlocutory

appeal in the county court, pursuant to Mass. R. Crim.

P. 15 (a) (2), as appearing in 474 Mass. 1501 (2016); the single

justice allowed the appeal to proceed in this court.

    2.    Discussion.    "In reviewing a decision on a motion to

suppress, we accept the judge's subsidiary findings absent clear

error but conduct an independent review of [the] ultimate

findings and conclusions of law" (quotations and citation

omitted).   Commonwealth v. Jones-Pannell, 472 Mass. 429, 431

(2015).   Here, reviewing the judge's conclusions of law requires

us to determine, among other things, whether the use of ALPR

technology by police constitutes a search under the Fourth

Amendment or art. 14.

    a.    ALPRs and constitutional search protections.     Under

both the Fourth Amendment and art. 14, a search implicates

constitutional protections when the government "intrudes on a

person's reasonable expectation of privacy" (citation omitted).

Commonwealth v. Almonor, 482 Mass. 35, 40 (2019).    "An
                                                                     8


individual has a reasonable expectation of privacy where (i) the

individual has manifested a subjective expectation of privacy in

the object of the search, and (ii) society is willing to

recognize that expectation as reasonable" (quotations and

citation omitted).5   Commonwealth v. Johnson, 481 Mass. 710, 715,

cert. denied, 140 S. Ct. 247 (2019).   See Katz v. United States,

389 U.S. 347, 361 (1967) (Harlan, J., concurring).

     The constitutional jurisprudence governing the

technological surveillance of public space has developed rapidly

in the last decade.   To place the current situation in the

proper context, it is necessary to review these developments and

their underlying reasoning at some length.

     i.   Expectations of privacy and technology.    As this court

and the United States Supreme Court interpret society's

reasonable expectations of privacy over time, the courts'

overarching goal is to "assure [the] preservation of that degree




     5 In this case, the judge did not find explicitly that the
defendant had manifested a subjective expectation of privacy.
We infer from the undisputed record, however, that the defendant
manifested a subjective expectation of privacy in his location
by choosing to meet his codefendant in a quiet residential area.
See Commonwealth v. Fulgiam, 477 Mass. 20, 33, cert. denied, 138
S. Ct. 330 (2017) (concluding that subjective prong was
satisfied based on record). See, e.g., United States v. Moore-
Bush, 381 F. Supp. 3d 139, 143 (D. Mass. 2019) ("the Court
infers from their choice of neighborhood that they subjectively
expected that their and their houseguests' comings and goings
over the course of eight months would not be surreptitiously
surveilled").
                                                                     9


of privacy against government that existed when the Fourth

Amendment [and art. 14 were] adopted."    Almonor, 482 Mass. at 54

(Lenk, J., concurring), quoting Carpenter v. United States, 138

S. Ct. 2206, 2214 (2018).   We have recognized the difficulty of

this enterprise as developing technology places "extraordinarily

powerful surveillance tool[s]" in the hands of police.     Almonor,

supra at 46.    See Johnson, 481 Mass. at 716.   While

acknowledging the usefulness of these tools for crime detection,

"both this court and the United States Supreme Court have been

careful to guard against the 'power of technology to shrink the

realm of guaranteed privacy' by emphasizing that privacy rights

'cannot be left at the mercy of advancing technology but rather

must be preserved and protected as new technologies are adopted

and applied by law enforcement.'"    Almonor, supra at 41, quoting

Johnson, supra.   See Kyllo v. United States, 533 U.S. 27, 34

(2001).   See also Olmstead v. United States, 277 U.S. 438, 473

(1928) (Brandeis, J., dissenting) (noting that courts must be

vigilant to guard against "[s]ubtler and more far-reaching means

of invading privacy [that] have become available to the

government").

    Like the Supreme Court, this court is guided "by historical

understandings of what was deemed an unreasonable search and

seizure when [the Constitutions were] adopted."     See Almonor,

482 Mass. at 43, citing Carpenter, 138 S. Ct. at 2214.    These
                                                                     10


historical understandings include the basic purposes underlying

the adoption of art. 14 and, later, the Fourth Amendment.      See

Almonor, supra, quoting Jenkins v. Chief Justice of the Dist.

Court Dep't, 416 Mass. 221, 229 (1993) ("we construe [art. 14]

in light of the circumstances under which it was framed, the

causes leading to its adoption, the imperfections hoped to be

remedied, and the ends designed to be accomplished").     See also

Carpenter, supra at 2213.   More specifically, we have recognized

that the underlying purposes of both art. 14 and the Fourth

Amendment are the need to "secure the privacies of life against

arbitrary power," and to "place obstacles in the way of a too

permeating police surveillance."   Almonor, supra at 53 (Lenk,

J., concurring), quoting Carpenter, supra at 2214.      Both warrant

further explanation in the context of emerging technology.

    A.   Arbitrary power.   The framers had first-hand experience

with abuses of arbitrary power under British rule.   Our cases

acknowledge that they wrote constitutional search protections in

"response to the reviled 'general warrants' and 'writs of

assistance' of the colonial era, which allowed British officers

to rummage through homes in an unrestrained search for evidence

of criminal activity."   See Carpenter, 138 S. Ct. at 2213,

quoting Riley v. California, 573 U.S. 373, 403 (2014).      See also

Commonwealth v. Blood, 400 Mass. 61, 71 (1987).   The

surveillance implications of new technologies must be
                                                                    11


scrutinized carefully, lest scientific advances give police

surveillance powers akin to these general warrants.   Just as

police are not permitted to rummage unrestrained through one's

home, so too constitutional safeguards prevent warrantless

rummaging through the complex digital trails and location

records created merely by participating in modern society.      See,

e.g., Almonor, 482 Mass. at 46 (police causing cellular

telephone to reveal real-time location contravenes reasonable

expectation of privacy); Commonwealth v. Augustine, 467 Mass.

230, 255 (2014), S.C., 470 Mass. 837 (2015) (reasonable

expectation of privacy exists in cellular site location

information [CSLI]6).   See also Carpenter, supra at 2217 ("A

person does not surrender all Fourth Amendment protection by

venturing into the public sphere").

     B.   Permeating police presence.   As the Supreme Court made

clear in Carpenter, courts analyzing the constitutional

implications of new surveillance technologies also should be

guided by the founders' intention "to place obstacles in the way

of a too permeating police surveillance."   Carpenter, 138 S. Ct.

at 2214, quoting United States v. Di Re, 332 U.S. 581, 595




     6 Cellular site location information "refers to a cellular
telephone service record or records that contain information
identifying the base station towers and sectors that receive
transmissions from a [cellular] telephone" (citation omitted).
Commonwealth v. Estabrook, 472 Mass. 852, 853 n.2 (2015).
                                                                   12


(1948).   Specifically, both this court and the Supreme Court

have recognized how advancing technology undercuts traditional

checks on an overly pervasive police presence because it (1) is

not limited by the same practical constraints that heretofore

effectively have limited long-running surveillance, (2) proceeds

surreptitiously, and (3) gives police access to categories of

information previously unknowable.

    As Justice Alito wrote in Jones, "[i]n the pre-computer

age, the greatest protections of privacy were neither

constitutional nor statutory, but practical.   Traditional

surveillance for any extended period of time was difficult and

costly and therefore rarely undertaken."   United States v.

Jones, 565 U.S. 400, 429 (2012) (Alito, J., concurring).     The

continuous, tireless, effortless, and absolute surveillance of

the digital age contravenes expectations of privacy that are

rooted in these historical and practical limitations.   For this

reason, when the duration of digital surveillance drastically

exceeds what would have been possible with traditional law

enforcement methods, that surveillance constitutes a search

under art. 14.   See, e.g., Augustine, 467 Mass. at 253.

    In addition, the surreptitious nature of digital

surveillance removes a natural obstacle to too permeating a

police presence by hiding the extent of that surveillance.

Resource constraints aside, we imagine Massachusetts residents
                                                                   13


would object were the police continuously to track every

person's public movements by traditional surveillance methods,

absent any suspicion at all.   Justice Sotomayor summed up these

first two concerns in a discussion of global positioning system

(GPS)7 monitoring:   "because [it] is cheap in comparison to

conventional surveillance techniques and, by design, proceeds

surreptitiously, it evades the ordinary checks that constrain

abusive law enforcement practices:    'limited police resources

and community hostility'" (citation omitted).    Jones, 565 U.S.

at 415–416 (Sotomayor, J., concurring).

     Finally, new surveillance techniques risk creating too

permeating a police presence by giving police access to "a

category of information otherwise unknowable."    Carpenter, 138

S. Ct. at 2218.   For example, with CSLI data "the Government can

now travel back in time to retrace a person's whereabouts . . .

[and] police need not even know in advance whether they want to

follow a particular individual, or when.    Whoever the suspect

turns out to be, he has effectively been tailed every moment of

every day for five years . . . ."    Id.   See Augustine, 467 Mass.



     7 A global positioning system (GPS) tracking system "allows
police to monitor and record the location of a vehicle [or an
individual] without the [target]'s knowledge" by ascertaining
the target's location via communication with satellites, and
then transmitting that location to a computer system that stores
it electronically. Commonwealth v. Connolly, 454 Mass. 808, 812
(2009).
                                                                    14


at 254.    Likewise, in Almonor, 482 Mass. at 46, this court

considered the capability of police to "ping" a cellular

telephone, causing it to reveal its real-time location data, and

observed that "[t]his extraordinarily powerful surveillance tool

finds no analog in the traditional surveillance methods of law

enforcement."

     These historical understandings inform our analysis as we

apply the test that originated more than fifty years ago in

Katz, 389 U.S. at 361 (Harlan, J., concurring), to determine

whether the collection and use of ALPR data constitutes a

search.

     ii.   Searches in public.   This founding-era guidance has

aided courts, even as technological advances in the surveillance

of public space have posed difficult questions to courts under

the "reasonable expectation of privacy" framework established in

Katz.   The tension derives from two contrasting sentences

contained in Katz itself.    First, Katz states that "[w]hat a

person knowingly exposes to the public, even in his own home or

office, is not a subject of Fourth Amendment protection."      Katz,

389 U.S. at 351.    For this reason, "[w]hether an expectation of

privacy is reasonable depends in large part upon whether that

expectation relates to information that has been exposed to the

public" (alteration, quotation, and citation omitted).     United

States v. Maynard, 615 F.3d 544, 558 (D.C. Cir. 2010), aff'd in
                                                                      15


part sub nom. Jones, 565 U.S. 400.       On the other hand, "[a]

person does not surrender all Fourth Amendment protection by

venturing into the public sphere."       Carpenter, 138 S. Ct.

at 2217.   For "what [someone] seeks to preserve as private, even

in an area accessible to the public, may be constitutionally

protected."   Katz, supra.    See id. at 354 (constitutionally

protected privacy interest in contents of telephone conversation

made from public telephone booth).       In short, while the Fourth

Amendment and art. 14 "protect[] people, not places," whether

something is knowingly exposed to the public remains a

touchstone in determining the reasonableness of a person's

expectation of privacy.    Id. at 351.    See Augustine, 467 Mass.

at 252; Commonwealth v. Billings, 42 Mass. App. Ct. 261, 265

(1997) (listing constitutional nonsearches based on knowing

exposure principle).

    A.     What is knowingly exposed.    Under this doctrine, police

observation of the exterior of an automobile is not a search

because it is "knowingly exposed."      See New York v. Class, 475

U.S. 106, 114 (1986) ("The exterior of a car, of course, is

thrust into the public eye, and thus to examine it does not

constitute a 'search'").     In Massachusetts, this reasoning

extends quite naturally to license plates.      In Commonwealth v.

Starr, 55 Mass. App. Ct. 590, 591 (2001), a police officer saw a

license plate on an automobile, located the plate number in a
                                                                    16


police database, and stopped the vehicle because the plates were

registered to a different vehicle.     Relying on the knowing

exposure principle of Katz, the court held that the defendant

had no reasonable expectation of privacy that would prevent an

officer from examining his license plate.     Starr, supra at 593-

594.8

        In United States v. Knotts, 460 U.S. 276, 285 (1983), the

Supreme Court applied the logic of "what is knowingly exposed"

to sanction the warrantless use of a radio "beeper"9 to assist

police in tracking a vehicle on a single journey.

        "A person traveling in an automobile on public
        thoroughfares has no reasonable expectation of privacy
        in his movements from one place to another. When [the
        codefendant] traveled over the public streets he
        voluntarily conveyed to anyone who wanted to look the
        fact that he was traveling over particular roads in a
        particular direction, the fact of whatever stops he
        made, and the fact of his final destination when he
        exited from public roads onto private property."

Id. at 281–282.    In so holding, the Knotts Court dismissed the

defendant's claim that, should he lose his case, "twenty-four



       Massachusetts requires that license plates be "displayed
        8

conspicuously," G. L. c. 90, § 6, and the failure to do so can
result in fines or imprisonment, see G. L. c. 90, § 23. These
requirements support the contention that there is no objectively
reasonable expectation of privacy in a license plate number, the
very purpose of which is to identify the vehicle to the
government.

       "A beeper is a radio transmitter, usually battery
        9

operated, which emits periodic signals that can be picked up by
a radio receiver." United States v. Knotts, 460 U.S. 276, 277
(1983).
                                                                   17


hour surveillance of any citizen of this country will be

possible, without judicial knowledge or supervision."      Id.

at 283.   The court went on to note, however, that "if such

dragnet-type law enforcement practices as respondent envisions

should eventually occur, there will be time enough then to

determine whether different constitutional principles may be

applicable."   Id. at 284.

    In this distinction, we recognize precisely the question

posed by this case:   whether Knotts, Starr, and the "knowing

exposure" principle of Katz control, as the Commonwealth

contends, or whether different constitutional principles apply,

as the defendant argues.     To answer, we must look to those cases

of emerging surveillance technology where we indeed have

determined that different constitutional principles govern.

    B.    Mosaic theory.     When new technologies drastically

expand police surveillance of public space, both the United

States Supreme Court and this court have recognized a privacy

interest in the whole of one's public movements.      See Carpenter,

138 S. Ct. at 2217 ("individuals have a reasonable expectation

of privacy in the whole of their physical movements"); Johnson,

481 Mass. at 716; Augustine, 467 Mass. at 248-249; Commonwealth

v. Rousseau, 465 Mass. 372, 382 (2013).

    The question first emerged in the context of a GPS device

affixed to a suspect's vehicle.     We ultimately concluded,
                                                                  18


consistent with Supreme Court precedent, that "the government's

contemporaneous electronic monitoring of one's comings and

goings in public places invades one's reasonable expectation of

privacy."   Rousseau, 465 Mass. at 382.   Next, in cases

addressing police access to CSLI, both this court and the

Supreme Court reaffirmed the same principle -- that it is

objectively reasonable for individuals to expect to be free from

sustained electronic monitoring of their public movements.     See

Augustine, 467 Mass. at 247-248.   See also Carpenter, 138 S. Ct.

at 2219.

     Both courts reached these conclusions, in part, by

distinguishing the relatively primitive beeper used in Knotts

from the encyclopedic, effortless collection of CSLI and GPS

data.   See Augustine, 467 Mass. at 252 ("There is no real

question that the government, without securing a warrant, may

use electronic devices to monitor an individual's movements in

public to the extent that the same result could be achieved

through visual surveillance" [emphasis added]).    See also

Carpenter, 138 S. Ct. at 2215, 2218 (distinguishing

"rudimentary" beeper used in Knotts to track single "discrete

automotive journey" from use of CSLI, which achieves "near

perfect surveillance, as if [the government] had attached an

ankle monitor to the phone's user").
                                                                   19


     Essentially, these cases articulate an aggregation

principle for the technological surveillance of public conduct,

sometimes referred to as the mosaic theory.10    When collected for

a long enough period, "the cumulative nature of the information

collected implicates a privacy interest on the part of the

individual who is the target of the tracking."    Augustine, 467

Mass. at 253.   See Jones, 565 U.S. at 416 (Sotomayor, J.,

concurring) ("when considering the existence of a reasonable

societal expectation of privacy in the sum of one's public

movements . . . I would ask whether people reasonably expect

that their movements will be recorded and aggregated in a manner

that enables the Government to ascertain, more or less at will,

their political and religious beliefs, sexual habits, and so on"

[emphasis added]).   A recent case in the United States District

Court for the District of Massachusetts summarized the idea

succinctly:   "Although these activities, taken one by one, may

not give rise to a reasonable expectation of privacy . . . , the




     10See, e.g., Kerr, The Mosaic Theory of the Fourth
Amendment, 111 Mich. L. Rev. 311, 320 (2012) ("The mosaic theory
requires courts to apply the Fourth Amendment search doctrine to
government conduct as a collective whole rather than in isolated
steps. Instead of asking if a particular act is a search, the
mosaic theory asks whether a series of acts that are not
searches in isolation amount to a search when considered as a
group. The mosaic theory is therefore premised on aggregation:
it considers whether a set of nonsearches aggregated together
amount to a search because their collection and subsequent
analysis creates a revealing mosaic").
                                                                   20


Court aggregates their sum total for its analysis."    United

States v. Moore-Bush, 381 F. Supp. 3d 139, 149 (D. Mass. 2019).

As the analogy goes, the color of a single stone depicts little,

but by stepping back one can see a complete mosaic.

    This aggregation principle or mosaic theory is wholly

consistent with the statement in Katz, 389 U.S. at 351, that

"[w]hat a person knowingly exposes to the public . . . is not a

subject of Fourth Amendment protection," because the whole of

one's movements, even if they are all individually public, are

not knowingly exposed in the aggregate.    As the United States

Court of Appeals for the District of Columbia Circuit explained:

    "the whole of a person's movements over the course of a
    month is not actually exposed to the public because the
    likelihood a stranger would observe all those movements is
    not just remote, it is essentially nil. It is one thing
    for a passerby to observe or even to follow someone during
    a single journey as he goes to the market or returns home
    from work. It is another thing entirely for that stranger
    to pick up the scent again the next day and the day after
    that, week in and week out, dogging his prey until he has
    identified all the places, people, amusements, and chores
    that make up that person's hitherto private routine."

Maynard, 615 F.3d at 560.

    A detailed account of a person's movements, drawn from

electronic surveillance, encroaches upon a person's reasonable

expectation of privacy because the whole reveals far more than

the sum of the parts.   "The difference is not one of degree but

of kind . . . ."   Id. at 562.   "Prolonged surveillance reveals

types of information not revealed by short-term surveillance,
                                                                     21


such as what a person does repeatedly, what he does not do, and

what he does ensemble."    Id.   Aggregated location data reveals

"a highly detailed profile, not simply of where we go, but by

easy inference, of our associations -- political, religious,

amicable and amorous, to name only a few -- and of the pattern

of our professional and avocational pursuits."      Commonwealth v.

Connolly, 454 Mass. 808, 834 (2009) (Gants, J., concurring),

quoting People v. Weaver, 12 N.Y.3d 433, 442 (2009).

    iii.    Constitutional implications of ALPRs.    With this

theoretical foundation in mind, we turn to the central question

of this case:   whether the use of ALPRs by the police invades an

objective, reasonable expectation of privacy.     Or, more

specifically, we must determine whether ALPRs produce a detailed

enough picture of an individual's movements so as to infringe

upon a reasonable expectation that the Commonwealth will not

electronically monitor that person's comings and goings in

public over a sustained period of time.     See, e.g., Augustine,

467 Mass. at 247-248.

    A.     ALPRs under the mosaic theory.   In determining whether

a reasonable expectation of privacy has been invaded, it is not

the amount of data that the Commonwealth seeks to admit in

evidence that counts, but, rather, the amount of data that the

government collects or to which it gains access.     See

Commonwealth v. Estabrook, 472 Mass. 852, 858-859 (2015), citing
                                                                   22


Augustine, 467 Mass. at 254 ("in terms of reasonable expectation

of privacy, the salient consideration is the length of time for

which a person's CSLI is requested, not the time covered by the

person's CSLI that the Commonwealth ultimately seeks to use as

evidence at trial").   In Rousseau, 465 Mass. at 376, 382, we

weighed the thirty-one days of GPS monitoring in the

constitutional analysis, not the data that placed the vehicle

near the suspected arsons on four specific dates.   Similarly, in

Carpenter, 138 S. Ct. at 2212-2213, the relevant period was the

127 days of CSLI data, not the data that placed the defendant

near the robberies on four particular days.11   For this reason,

our constitutional analysis ideally would consider every ALPR


     11Our holding in Commonwealth v. Johnson, 481 Mass. 710,
722, cert. denied, 140 S. Ct. 247 (2019), is not to the
contrary. There, we determined that the imposition of GPS
monitoring on a specific probationer was a search, but a
reasonable one in the circumstances. Id. at 720. We then
concluded that the subsequent examination of the probationer's
location data by law enforcement was not a search, because the
probationer had no reasonable expectation of privacy in his
location; he knew he was wearing a GPS ankle monitor that was
transmitting his location to the government. See id. at 722-
725, 728. As an ancillary rationale, we emphasized that the
police only sought the defendant's location at the specific
times of various robberies, thus minimizing the intrusion. Id.
at 727-728. Throughout, we emphasized the importance of the
individual's status as a probationer, contrasting his
expectations of privacy with those of a nonprobationer. Id.
at 724 ("There is no question that the reasonableness of any
expectations of privacy held by a probationer knowingly subject
to GPS monitoring as a condition of probation is far different
from the reasonableness of the expectations of privacy held by
individuals who are surreptitiously tracked by law
enforcement").
                                                                   23


record of a defendant's vehicle that had been stored and

collected by the government up to the time of the defendant's

arrest.   That information, however, is not in the record before

us.

      With enough cameras in enough locations, the historic

location data from an ALPR system in Massachusetts would invade

a reasonable expectation of privacy and would constitute a

search for constitutional purposes.   The one-year retention

period indicated in the EOPSS retention policy certainly is long

enough to warrant constitutional protection.   See Augustine, 467

Mass. at 254–255 ("tracking of the defendant's movements [by

CSLI] in the urban Boston area for two weeks was more than

sufficient to intrude upon the defendant's expectation of

privacy safeguarded by art. 14"); Rousseau, 465 Mass. at 382

(thirty-one days of GPS monitoring was sufficient duration to

conclude monitoring was search).   Like CSLI data, ALPRs allow

the police to reconstruct people's past movements without

knowing in advance who police are looking for, thus granting

police access to "a category of information otherwise [and

previously] unknowable."   See Carpenter, 138 S. Ct. at 2218.

Like both CSLI and GPS data, ALPRs circumvent traditional

constraints on police surveillance power by being cheap

(relative to human surveillance) and surreptitious.
                                                                   24


     Of course, the constitutional question is not merely an

exercise in counting cameras; the analysis should focus,

ultimately, on the extent to which a substantial picture of the

defendant's public movements are revealed by the surveillance.

For that purpose, where the ALPRs are placed matters too.     ALPRs

near constitutionally sensitive locations -- the home, a place

of worship, etc. -- reveal more of an individual's life and

associations than does an ALPR trained on an interstate highway.

A network of ALPRs that surveils every residential side street

paints a much more nuanced and invasive picture of a driver's

life and public movements than one limited to major highways

that open into innumerable possible destinations.   For while no

ALPR network is likely to be as detailed in its surveillance as

GPS or CSLI data, one well may be able to make many of the same

inferences from ALPR data that implicate expressive and

associative rights.12   See American Civ. Liberties Union Found.

of S. Cal. v. Superior Court of Los Angeles County, 3 Cal. 5th




     12 The International Association of Chiefs of Police has
warned that collecting ALPR data from multiple sources creates
the risk "that individuals will become more cautious in the
exercise of their protected rights of expression, protest,
association, and political participation because they consider
themselves under constant surveillance." International
Association of Chiefs of Police, Privacy Impact Assessment
Report for the Utilization of License Plate Readers, at 13
(Sept. 2009), https://www.theiacp.org/sites/default/files/all
/k-m/LPR_Privacy_Impact_Assessment.pdf [https://perma.cc/M2T4
-G5F5].
                                                                 25


1032, 1044 (2017) (ALPR data "could potentially reveal where [a]

person lives, works, or frequently visits").

     Similarly, with cameras in enough locations, the hot list

feature could implicate constitutional search protections by

invading a reasonable expectation of privacy in one's real-time

location.   If deployed widely enough, ALPRs could tell police

someone's precise, real-time location virtually any time the

person decided to drive, thus making ALPRs the vehicular

equivalent of a cellular telephone "ping."   See Almonor, 482

Mass. at 55 (Lenk, J., concurring) ("When police act on real-

time information by arriving at a person's location, they signal

to both the individual and his or her associates that the person

is being watched. . . .   To know that the government can find

you, anywhere, at any time is -- in a word -- 'creepy'").   Of

course, no matter how widely ALPRs are deployed, the exigency

exception to the warrant requirement would apply to this hot

list feature.13


     13Order TRF-11 gives a nonexclusive list of reasons for
which authorized users may manually place a license plate on a
hot list, including "AMBER" alerts, missing child alerts,
missing college student bulletins, and "be on the look out"
alerts. In these circumstances, the use of real-time alerts may
be constitutionally permissible under the exigent circumstances
exception to the warrant requirement. See Riley v. California,
573 U.S. 373, 388, 391, 402 (2014) (repeatedly noting how
exigent circumstances exception might apply to warrant
requirement for cellular telephone searches); Warden, Md.
Penitentiary v. Hayden, 387 U.S. 294, 298–299 (1967) ("The
Fourth Amendment does not require police officers to delay in
                                                                  26


     Finally, like carrying a cellular telephone, driving is an

indispensable part of modern life, one we cannot and do not

expect residents to forgo in order to avoid government

surveillance.

     B.   Number and location of ALPR data collection points in

this case.   On this record, however, we need not, and indeed

cannot, determine how pervasive a system of ALPRs would have to

be to invade a reasonable expectation of privacy.   While a

testifying expert alluded to cameras "all over the [S]tate," the

record is silent as to how many of these cameras currently

exist,14 where they are located, and how many of them detected

the defendant.

     Therefore, for this case, we consider the constitutional

import of four cameras placed at two fixed locations on the ends

of the Bourne and Sagamore bridges.   "Fourth Amendment [and art.

14] cases must be decided on the facts of each case, not by

extravagant generalizations.   '[W]e have never held that




the course of an investigation if to do so would gravely
endanger their lives or the lives of others"). Similarly, the
use of ALPRs to find a vehicle reported stolen would not be
constitutionally impermissible, because the driver of a stolen
vehicle does not have a reasonable expectation of privacy in the
location of someone else's automobile.

     14The amici submit that, in 2015, there were 168 ALPR
cameras in operation in Massachusetts. The information provided
by the amici was not before the motion judge and remains
untested by the adversarial process.
                                                                   27


potential, as opposed to actual, invasions of privacy constitute

searches for purposes of the Fourth Amendment.'"    Dow Chem. Co.

v. United States, 476 U.S. 227, 238 n.5 (1986), quoting United

States v. Karo, 468 U.S. 705, 712 (1984).

    "There is no real question that the government, without

securing a warrant, may use electronic devices to monitor an

individual's movements in public to the extent that the same

result could be achieved through visual surveillance."

Augustine, 467 Mass. at 252.    It is an entirely ordinary

experience to drive past a police officer in a cruiser observing

traffic on the side of the road, and, of course, an officer may

read or write down a publicly displayed license plate number.

See Starr, 55 Mass. App. Ct. at 594.    In this way, a single

license plate reader is similar to traditional surveillance

techniques.    On the other hand, four factors distinguish ALPRs

from an officer parked on the side of the road:    (1) the policy

of retaining the information for, at a minimum, one year;

(2) the ability to record the license plate number of nearly

every passing vehicle; (3) the continuous, twenty-four hour

nature of the surveillance; and (4) the fact that the recorded

license plate number is linked to the location of the

observation.    These are enhancements of what reasonably might be

expected from the police.
                                                                   28


     The limited number of cameras and their specific

placements, however, also are relevant in determining whether

they reveal a mosaic of location information that is

sufficiently detailed to invade a reasonable expectation of

privacy.   The cameras in question here gave police only the

ability to determine whether the defendant was passing onto or

off of the Cape at a particular moment, and when he had done so

previously.   This limited surveillance does not allow the

Commonwealth to monitor the whole of the defendant's public

movements, or even his progress on a single journey.     These

particular cameras make this case perhaps more analogous to

CSLI, if there were only two cellular telephone towers

collecting data.    Such a limited picture does not divulge "the

whole of [the defendant's] physical movements," Carpenter, 138

S. Ct. at 2217, or track enough of his comings and goings so as

to reveal "the privacies of life."    Id., quoting Riley, 573 U.S.

at 403.    See Boyd v. United States, 116 U.S. 616, 630 (1886).

     While we cannot say precisely how detailed a picture of the

defendant's movements must be revealed to invoke constitutional

protections, it is not that produced by four cameras at fixed

locations on the ends of two bridges.15   Therefore, we conclude


     15In declining to establish a bright-line rule for when the
use of ALPRs constitutes a search, we recognize this may bring
some interim confusion. We trust, however, that as our cases
develop, this constitutional line gradually and appropriately
                                                                  29


that the limited use of ALPRs in this case does not constitute a

search within the meaning of either art. 14 or the Fourth

Amendment.16

     b.   Defendant's other arguments.   We turn to the

defendant's remaining claims.   He argues that various evidence

should be suppressed because (1) the Barnstable police did not

show a written policy governing ALPR use, and the State police

ALPR policy, adopted by the Barnstable police, is deficient and

constitutionally inadequate; (2) the use of ALPR systems

violates 18 U.S.C. §§ 2701-2712, the Federal Stored

Communications Act (SCA), and 18 U.S.C. §§ 2510-2523, the

Federal Electronic Communications Privacy Act (ECPA); (3) the

court should adopt the doctrine of target standing; and (4) the

incriminating statements were involuntarily coerced through




will come into focus. "The judiciary risks error by elaborating
too fully on the Fourth Amendment [or art. 14] implications of
emerging technology before its role in society has become
clear." Ontario v. Quon, 560 U.S. 746, 759 (2010).

     16The defendant argues that, if the ALPR data were
suppressed, there would have been no probable cause for his
arrest. Because we conclude that the use of the ALPR data was
not a search in the constitutional sense, the data gleaned from
the use of the ALPR properly is considered in the probable cause
analysis. We discern no error in the motion judge's
determination that there was probable cause to arrest the
defendant when the ALPR data is included in that analysis.
                                                                    30


police trickery in violation of the defendant's Miranda rights.17

We conclude that each of these arguments is without merit.

     i.   Role of police policies.    The defendant argues that,

because the Barnstable police did not introduce a written policy

governing police use of ALPR data, and because the State police

policy, Order TRF-11, is inadequately specific, the evidence

against him must be suppressed.      In support of this argument,

the defendant relies on cases where we have required police to

introduce evidence of a written policy to justify warrantless

inventory searches or to demonstrate "that sobriety checkpoints

be governed by standard, neutral guidelines that clearly forbid

the arbitrary selection of vehicles to be initially stopped."

Commonwealth v. Murphy, 454 Mass. 318, 323 (2009) (sobriety

checkpoint guidelines).   See Commonwealth v. Bishop, 402 Mass.

449, 451 (1988) ("art. 14 . . . requires the exclusion of

evidence seized during an inventory search not conducted

pursuant to standard police procedures, which procedures, from

now on, must be in writing").




     17In addition to the arguments discussed here, the
defendant contends that the seizure of his bail money was
unlawful. The seizure of the defendant's bail money was not
part of the judge's decision on the motion to suppress and
therefore is not properly before this court. See Mass. R. Crim.
P. 15 (a) (2), as appearing in 474 Mass. 1501 (2016).
Accordingly, we do not consider it.
                                                                     31


     This argument is unavailing.     These cases involve the

reasonableness of a search or seizure conducted under specific

exceptions to the warrant requirement, not the threshold

constitutional question whether a search or seizure has occurred

at all.     Detailed policy guidelines for police use of ALPRs well

may be a "good idea," Riley, 573 U.S. at 398, but their

existence or lack thereof does not determine the constitutional

question.

     ii.     Statutory claims.   The defendant argues further that

the government's use of ALPR data is subject to the SCA and the

ECPA.     Neither statute, however, is applicable.18   The SCA

prevents the government from compelling a "provider of

electronic communication service" to produce such communications

without following certain procedures.      See 18 U.S.C. § 2703.

Here, the government did not compel production of electronic

communications, but, rather, created and used them in the first

instance.     Similarly, the ECPA regulates the interception of




     18The defendant's reliance on G. L. c. 214, § 1B, is
similarly misplaced. That statute creates a cause of action for
tort liability to "protect[] individuals from 'disclosure of
facts . . . that are of a highly personal or intimate nature
when there exists no legitimate, countervailing interest.'" Doe
v. Brandeis Univ., 177 F. Supp. 3d 561, 616 (D. Mass. 2016),
quoting Dasey v. Anderson, 304 F.3d 148, 153–154 (1st Cir.
2002). While it conceivably could support tort litigation
against government actors (subject, of course, to sovereign
immunity constraints), it has no application to the criminal
suppression context.
                                                                    32


wire, oral, and electronic communications.    See 18 U.S.C.

§ 2511.    As the motion judge correctly determined, it would

produce an absurd reading of the statute to conclude that

officers were intercepting their own communications when

receiving real-time alerts.    See 18 U.S.C. § 2511(2)(c) ("It

shall not be unlawful under this chapter for a person acting

under color of law to intercept a wire, oral, or electronic

communication, where such person is a party to the communication

. . .").    See also 18 U.S.C. § 2510(5)(a) (exempting any

telephone or equipment used by law enforcement officers in

course of their duties from types of devices that can be used to

"intercept").

    iii.    Target standing.   The defendant also argues that this

court should adopt the doctrine of "target standing," which

would give him standing to contest the search of his codefendant

because he was one of that search's secondary targets.       See

Commonwealth v. Santiago, 470 Mass. 574, 577 (2015).     It would

allow him "to assert that a violation of the Fourth Amendment

rights of a third party entitled him to have evidence suppressed

at his trial."   Id.   The United States Supreme Court has

rejected the doctrine with respect to the Fourth Amendment.

Rakas v. Illinois, 439 U.S. 128, 132-133 (1978).    We also

repeatedly have declined to adopt target standing under art. 14,

but have left open the possibility of applying the doctrine in
                                                                    33


cases of "distinctly egregious police conduct."    See Santiago,

supra at 577-578.   Nothing in this record suggests "distinctly

egregious police conduct."   Therefore, the defendant does not

have target standing to challenge evidence seized from his

codefendant.

    iv.   Miranda waiver.    The defendant argues that his waiver

of his Miranda rights and the statements he made to police were

involuntary because the officers repeatedly told him that he was

not under arrest.   The tests to determine whether a Miranda

waiver was voluntary and for the voluntariness of a statement

are "essentially the same" (citation omitted).     Commonwealth v.

Newson, 471 Mass. 222, 229 (2015).

    With respect to the Miranda issue, the motion judge found

the following.   First, the defendant was under arrest at the

time he was handcuffed during the roadside stop.    He properly

and carefully was advised of his Miranda rights immediately

after being handcuffed, and again at the police station.     He

understood these rights both times.

    We agree with the motion judge that questions asked at the

roadside and at the police station constituted custodial

interrogation.   Considering the totality of the circumstances,

the only factor indicating a lack of voluntariness was the

officers' statements that the defendant was not under arrest and

that he might avoid arrest by giving the information he
                                                                  34


initially promised.    The defendant argues that the waiver and

the statements were involuntary based on these deceptive

representations.

    "[D]eception or trickery does not necessarily compel

suppression of the confession or admission but, instead, is one

factor to be considered in a totality of the circumstances

analysis."   Newson, 471 Mass. at 230, quoting Commonwealth v.

Tremblay, 460 Mass. 199, 208 (2011).    In Newson, supra, this

court held that even if an officer engaged in deceit or trickery

by telling a defendant that he was not under arrest, such deceit

would not be enough to demonstrate involuntariness.   Here, the

facts are essentially the same.   Therefore, we do not disturb

the judge's finding that the Commonwealth proved beyond a

reasonable doubt that the statements and the Miranda waiver were

voluntary.

    3.   Conclusion.   While we recognize that the widespread use

of ALPRs in the Commonwealth could implicate constitutional

protections against unreasonable searches, the limited use of

the technology in this case does not.

                                    Order denying motions to
                                      suppress affirmed.
     GANTS, C.J. (concurring).   I agree with the court that, if

the State police had obtained historical locational data

regarding the defendant's vehicle from enough automatic license

plate readers (ALRPs) in enough locations, the mosaic that such

collection would create of the defendant's movements "would

invade a reasonable expectation of privacy and would constitute

a search for constitutional purposes."   Ante at      .    I also

agree with the court that the locational information regarding

the defendant that was obtained from four ALPRs at two fixed

locations on two bridges falls short of creating the type of

mosaic that would constitute a search within the meaning of

either art. 14 of the Massachusetts Declaration of Rights or the

Fourth Amendment to the United States Constitution.       And I agree

that the court is correct to forbear from declaring in this case

"precisely how detailed a picture of the defendant's movements

must be revealed to invoke constitutional protections."       Id.

at   .   I write separately not to attempt to answer how

detailed the picture must be but to suggest an analytical

framework that might prove useful in future cases.

     It is important to recognize that this is the first case we

have encountered where the State police are collecting and

storing a vast amount of locational data, from which they

potentially might conduct a targeted search of locational

information for a particular person or vehicle without probable
                                                                    2


cause and without court authorization.   Cellular telephone

companies possess even more locational data that can track the

movements of a cellular telephone (and thus the person in

possession of it), but law enforcement may obtain that

information from these companies only through a search warrant

or court order.

    Under our case law, a search warrant based on probable

cause is required for law enforcement to obtain more than six

hours of historical telephone call cellular site location

information (CSLI) regarding a particular individual.    See

Commonwealth v. Estabrook, 472 Mass. 852, 854 (2015);

Commonwealth v. Augustine, 467 Mass. 230, 255 (2014), S.C., 470

Mass. 837 (2015).   A court order under 18 U.S.C. § 2703 based on

"specific and articulable facts" that show "reasonable grounds

to believe" that the records "are relevant and material to an

ongoing criminal investigation" suffices under art. 14 to obtain

six hours or less of CSLI regarding a particular individual.

See Estabrook, supra at 855 n.4, 858.    If a law enforcement

agency possessed comparable historical locational data that

could produce a mosaic of an individual's movements equivalent

to that produced by CSLI, whether because it purchased bulk CSLI

data from a vendor or because it had a vast array of ALPRs or

surveillance cameras using facial recognition software, we would

require law enforcement to obtain a search warrant based on
                                                                     3


probable cause before it could retrieve the locational data for

that mosaic regarding a targeted individual.

    But what if the historical locational information regarding

a targeted individual that can be obtained from data in the

possession of a law enforcement agency could yield a mosaic of

location points that is less than that created by CSLI but

greater than the four location points established in this

record?    Pragmatically, I submit we have two alternatives.   Our

first option is to determine based on the facts of a particular

case when the locational mosaic of a targeted individual's

movements crosses the threshold of the reasonable expectation of

privacy.    A mosaic above that threshold would require a search

warrant based on probable cause, but a mosaic below that

threshold would not require any court authorization.

    Alternatively, we could strike a balance analogous to that

struck by the United States Supreme Court in Terry v. Ohio, 392

U.S. 1, 21 (1968), and decide that there are two locational

mosaic thresholds:    a lesser threshold that may be permissibly

crossed with a court order supported by an affidavit showing

reasonable suspicion and a greater threshold that is permissibly

crossed only with a search warrant supported by probable cause.

The reasonable suspicion standard would require "specific and

articulable facts" demonstrating reasonable suspicion that the

targeted individual has committed, is committing, or will commit
                                                                   4


a crime, see id. at 21-22, and that there are reasonable grounds

to believe that the data obtained from the query are relevant

and material to an investigation of the crime.   The reasonable

suspicion standard is different from and more exacting than the

standard required under 18 U.S.C. § 2703 to obtain six hours or

less of CSLI, which requires only "specific and articulable

facts" that show "reasonable grounds to believe" that the

records "are relevant and material to an ongoing criminal

investigation."

    This second alternative would mean that law enforcement

agencies would need to obtain court authorization more often

before retrieving targeted individual historical locational

information in their possession because queries that would not

require a showing of probable cause might still require a

showing of reasonable suspicion.   But the benefit to law

enforcement would be that, if the police sought a court order

based on reasonable suspicion and a reviewing court determined

that the query sought locational data that could yield a mosaic

of movement requiring a showing of probable cause, the search

would not be found unconstitutional (and the information

collected would not be suppressed) if the reviewing court found

that the affidavit supported a finding of probable cause.     In

contrast, where no court order was obtained and a reviewing

court determined that probable cause or reasonable suspicion was
                                                                    5


required to support the retrieval of historical locational

information, the data retrieved from the query would have to be

suppressed even if law enforcement could have met the applicable

standard.

    Regardless of which alternative the court ultimately

chooses, a reviewing court will need to know the extent of the

mosaic that was possible from the retrieval of historical

locational information regarding the movements of a targeted

individual, because only then can the court accurately determine

whether the threshold had been crossed.   Therefore, unless the

law enforcement agency has sought prior court approval to search

for particularized locational data in its possession, the agency

will have to preserve each and every search query for the

retrieval of historical locational information regarding a

targeted individual.   For instance, if the State police maintain

1,000 ALPRs at different locations throughout the Commonwealth,

it matters whether they searched for a suspect's vehicle from

the data yielded by all 1,000 cameras or only by four cameras,

and it matters whether they gathered this data for one day or

one hundred days.   And regardless of whether a court authorized

the search, the agency must preserve the historical locational

data regarding a particular individual that the agency retrieved

as a result of such queries from the data in its possession,

even when that exceeds the amount of data that the agency uses
                                                                  6


in an investigation or at trial.   Cf. Estabrook, 472 Mass. at

859 ("the salient consideration is the length of time for which

a person's CSLI is requested, not the time covered by the

person's CSLI that the Commonwealth ultimately seeks to use as

evidence at trial").   And the agency must make this preserved

data and search request available in discovery when sought by

the defendant.   Only then will a court have the information it

needs to determine whether the retrieval of locational

information regarding a targeted individual crossed a

constitutional threshold that requires court authorization and

either reasonable suspicion or probable cause.
