Court Opinion

ID: 4119665
Source: CourtListenerOpinion
Date Created: 2017-01-27 22:41:44.844526+00
Date Added: 2024-06-11T14:49:47.055952
License: Public Domain

Transmission by a Wireless Carrier of Information Regarding
  a Cellular Phone User’s Physical Location to Public Safety
  Organizations

Neither 47 U.S.C. § 1002(a) nor the Fourth Amendment o f the Constitution prohibits a wireless car­
   rier’s transmission to local public safety organizations o f information regarding the physical loca­
   tion of a caller who uses a cellular telephone to dial the 911 emergency line.

Although 18 U.S.C. §2703 would apparently apply to the carrier’s transmission of such location infor­
   mation to public safety organizations, the caller, by dialing 911, has impliedly consented to such
   disclosure, thus permitting the federal government to require the carrier to disclose such information
   without a warrant or court order.

                                                                                                September 10, 1996

          M e m o r a n d u m O p in io n   for th e   A c t in g A s s is t a n t A t t o r n e y G e n e r a l
                                              C r im in a l D iv is io n

   Y ou have asked for our opinion as to whether 47 U.S.C. § 1002(a) prohibits
a wireless carrier’s transmission to local public safety organizations of information
regarding the physical location of a caller who uses a cellular telephone to dial
the 911 emergency line. In addition, you have inquired as to the constraints, if
any, imposed by the Fourth Amendment on such a transmission.1 As set forth
in detail below, we conclude that § 1002(a), by its terms, does not prohibit such
transmission of location information. Although you have not inquired as to the
applicability of 18 U.S.C. § 2703(c), we conclude that, while the provision would
apparently apply to the carrier’s transmission of such location information to pub­
lic safety organizations, the caller, by dialing 911, has impliedly consented to
such disclosure, thus permitting the federal government to require the carrier to
disclose such information without a warrant or court order. Finally, the Fourth
Amendment does not prohibit such transmission both because of the caller’s im­
plied consent to the disclosure and because a caller who dials 911 has neither
an actual nor a reasonable expectation of privacy with regard to his whereabouts
at the time of the call.

  1 Memorandum for W alter E. Dellinger, Assistant Attorney General, Office o f Legal Counsel, from John C. Keeney,
Acting Assistant Attorney G eneral, Criminal Division, Re: Request far a Legal Opinion from the Federal Communica­
tions Commission as to the Applicability o f 47 U.S.C. § 1002(a) to the Transmission to Local Public Safety Agencies
o f the Physical Location o f a Cellular Telephone Caller Who Dials the 911 Emergency Line (May 13, 1996).

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                                               BACKGROUND

A. F acts

   In its recently issued rule regarding Compatibility of Wireless Services With
Enhanced 911 ( “ E-911” ), the Federal Communications Commission (the “ FCC” )
established a timetable for the development and deployment of new technologies
through which wireless carriers (cellular telephone companies) will automatically
provide a designated public safety answering point (“ PSAP” ) 2 with information
regarding the physical location of a caller who dials 911 on a wireless cellular
telephone. Commercial Mobile Radio Services, 47 C.F.R. §§20.3, 20.18 (1996).3
This information will significantly enhance the effectiveness of wireless 911 serv­
ices by helping emergency service personnel locate the caller and more rapidly
and accurately determine where the emergency has occurred.
   The implementation and deployment of enhanced 911 features and functions
will be accomplished in two phases. In phase one, covered carriers must relay
to the PSAP the 911 caller’s telephone number and the location of the cell site
or base station through which the call originates. See id. §20.18(d). This informa­
tion will identify the caller’s location only in quite general terms,4 but will enable
emergency service providers to call back if a 911 call is disconnected. See id.
We understand that the information provided in phase one is currently available
to wireless carriers, as it is regularly captured by them as part of their transmission
of calls from cellular phones,5 but some carriers must develop the ability to pass
it on to a third party.
   A more precise identification of the caller’s location will occur in phase two,
when the carrier must provide the designated PSAP with the physical location
of the mobile unit making the call by longitude and latitude within a radius of
125 meters in 67% of all cases. See id. § 20.18(e). According to FCC representa­
tives, the more precise location determination required in phase two will occur

    2 A public safety answering point is a facility designated to receive 911 calls and route them to emergency service
personnel. See A l C.F.R. §20.3.
    3 An E -9 11 system automatically identifies on a screen at the PSAP the telephone num ber and geographical location
from which the call was made. This system permits a more efficient response to calls received, mcluding silent
calls, and deters false alarms, because such calls are capable o f being traced. In many jurisdictions, E-911 systems
are already operational for landline phones, identifying the telephone num ber and the address associated with that
telephone number. The address o f the subscriber to the cellular telephone will often be insufficient to identify the
c aller’s physical location at the time of a call, however, because cellular telephones are mobile and calls are frequently
made from som eplace other than the c aller’s address. The need for this critical information regarding the location
o f the caller was the impetus for the new F C C rule.
    4The physical size o f a cell depends upon the density o f use: it could encompass only a few blocks in a populated
city, or m iles in a rural area.
    5 W hen a cellular caller makes a cal], the carrier captures his signal (his electronic serial number) and the data
carried on that signal, which is generally a mobile identification number ( “ M IN” ). A MIN is a 34-bit binary number
that a cellular handset transm its as part o f the process o f identifying itself to wireless networks. Each handset has
one M IN, which is derived from the ten-digit North A merican Numbering Plan telephone number that is generally
program m ed into the handset by a provider when it initiates service for a new subscriber. See id. §20.18. The
carrier’s records include transactional information, such as the caller’s address, associated with the MIN.

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    Transmission by a Wireless Carrier o f Information Regarding a Cellular Phone User's Physical
                               Location to Public Safety Organizations

through the development of new technologies enabling the carrier to combine and
analyze information regarding the strength, angle and timing of the caller’s signal
measured at two or more cell sites. A caller’s signal, and its strength, are already
often picked up by more than one cell site. In addition, many cell sites have
sectorized antennas, and, depending upon the angle of the signal’s arrival, a par­
ticular antenna will pick up the signal, thus informing the carrier what sector of
the cell the caller is located in. Finally, each site records the arrival time of a
signal. By developing new computer programs, switching technology, protocols
and network architecture, the carrier will be able to combine and analyze all of
this information— the strength of the signal at each of the cell sites picking up
the signal, the sector of a cell from which a signal emanates, and the time that
it takes for the signal to arrive at one cell site compared to other sites— to identify
more precisely the caller’s location.

B. Relevant Statutory Provisions

   The Communications Assistance for Law Enforcement Act of 1994
(“ CALEA” ), among other things, requires telecommunications carriers to ensure
that their equipment is capable of permitting the government (pursuant to a court
order or other lawful authorization) to access certain “ call-identifying informa­
tion” 6 that is reasonably available to the carrier. 47 U.S.C. § 1002(a)(2). CALEA
includes limitations, however, and specifically prohibits telecommunications car­
riers from providing the government with “ information acquired solely pursuant
to the authority for pen registers and trap and trace devices (as defined in section
3127 of title 18) . . . that may disclose the physical location of the subscriber
(except to the extent that the location may be determined from the telephone num­
ber).” Id. § 1002(a)(2)(B).7 Section 3127 of title 18 (part of the Electronic Com­
munications Privacy Act of 1986 (“ ECPA” )) in turn prohibits the installation
or use of pen registers and trap and trace devices absent a court order, with the
exception of particular uses by providers of electronic or wire communication
services.8
   6 “ The term ‘call-identifying information’ means dialing or signaling information that identifies the origin, direc­
tion, destination, or termination o f each communication generated or received by a subscriber by means o f any
equipment, facility, or service o f a telecommunications carrier.” 47 U.S.C. § 1001(2).
   7 J8 U.S.C. §3127 defines “ pen register” and ‘‘trap and trace device” as follows:
        (3) the term ‘pen register’ means a device which records or decodes electronic or other impulses which
      identify the numbers dialed o r otherwise transmitted on the telephone line to which such device is attached,
      but such term does not include any device used by a provider or customer o f a wire or electronic commu­
      nication service for billing, o r recording as an incident to billing, for communications services provided
      by such provider o r any device used by a provider or customer o f a wire communication service for cost
      accounting or other like purposes in the ordinary course of its business;
       (4) the term ‘trap and trace device’ means a device which captures the incoming electronic or other
     impulses which identify the originating number o f an instrument or device from which a wire or electronic
     communication was transmitted.
  8 18 U.S.C. §3121 provides in pertinent part’
                                                                                                          Continued

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                             Opinions o f the Office o f Legal Counsel in Volume 20

   Another provision of ECPA, 18 U.S.C. §2703, “ Requirements for governmental
access,” sets forth the terms under which carriers may provide governmental enti­
ties with information relating to electronic communications. In particular,
§ 2703(c) provides that a carrier shall only disclose a record or other information
pertaining to one of its customers (excluding the contents of communications cov­
ered elsewhere in the section) to a governmental entity when the governmental
entity obtains a warrant, a court order or the consent of the customer.9

                                                    ANALYSIS

A. Section 1002(a) Does Not Prohibit Wireless Carriers From Transmitting
Information Regarding the Physical Location o f Cellular Telephone Callers to
Public Safety Agencies

   By its terms, 47 U.S.C. § 1002(a)(2) does not prohibit a wireless carrier’s trans­
mission of physical location information as required by the new FCC rule. As
set forth above, § 1002(a)(2) only prohibits carriers from providing physical loca­
tion information “ acquired solely pursuant to the authority [under 18 U.S.C.
§3127] for pen registers and trap and trace devices.” The physical location of
a cellular caller would not be obtained pursuant to legal authority requested and
obtained by law enforcement officers as part of a government-initiated investiga­
tion, but instead pursuant to the recently issued FCC rule in response to an individ­
ual’s request for help. Indeed, the cellular caller’s physical location would not
be determined by use of a pen register or trap and trace device at a ll,10 but rather
   (a) In general. — Except as provided in this section, no person may install or use a pen register or a trap and
trace device without first obtaining a court order under section 3123 of this title or under the Foreign Intelligence
Surveillance Act o f 1978 (50 U.S.C. 1801 e t seq.).
   (b) Exception.— The prohibition of subsection (a) does not apply with respect to the use o f a pen register or
a trap and trace device by a provider of electronic or wire communication service—
      (1) relating to the operation, maintenance, and testing o f a wire or electronic communication service or
      to the protection o f the rights or property o f such provider, or to the protection o f users o f that service
      from abuse o f service or unlawful use o f service; or
     (2) to record the fact that a wire or electronic communication was initiated or completed in order to protect
     such provider, another provider furnishing service toward the completion of the wire communication, or
     a user o f that service, from fraudulent, unlawful o r abusive use o f service; or
      (3) where the consent o f the user o f that service has been obtained.
   9 A provider o f electronic communication service . . . shall disclose a record or other information pertaining to
a subscriber to o r custom er o f such service (not including the contents o f communications covered by subsection
(a) or (b) o f this section) to a governmental entity only when the governmental entity—
         (i) obtains a w arrant issued under the Federal Rules o f Criminal Procedure or equivalent State warrant;
       (ii) obtains a court order for such disclosure under subsection (d) of this section; or
         (iii) has the consent o f the subscriber o r custom er to such disclosure.
18 U .S.C. § 2 7 03(c)(l)(B ). Section 2703(c)(1)(C) provides that a carrier shall disclose certain transactional informa­
tion, including the name, address and telephone num ber o r other subscriber number, o f a custom er when the govern­
m ental entity utilizes an authorized administrative subpoena.
   10 A lthough pen registers and trap and trace devices would be used to obtain the caller's telephone num ber and
to relay the call to the PSAP, they would not provide any information on the actual physical location o f the cellular
caller.

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    Transmission by a Wireless Carrier o f Information Regarding a Cellular Phone U ser's Physical
                               Location to Public Safety Organizations

by advanced technologies that aggregate and analyze the strength and angle of
the caller’s signal measured at various cell sites. At the very least, it certainly
cannot be said that the caller’s physical location would be determined “ solely”
through use of a pen register or trap and trace device. 47 U.S.C. § 1002(a). Thus
§ 1002 does not prohibit a telecommunications carrier from transmitting to a public
safety organization the physical location information pertaining to a cellular caller
required by the FCC rule.11

B. 18 U.S.C. §2703 Permits Wireless Carriers to Transmit to Public Safety
Authorities the Physical Location of Cellular Callers Dialing 911 Because Such
Callers Have Impliedly Consented to Such Disclosure

  As set forth above, 18 U.S.C. §2703 requires wireless carriers to obtain a war­
rant, a court order or the consent of the customer before disclosing to govern­
mental authorities information relating to such customer. Although the disclosure
of information regarding the physical location of a customer would likely fall
within this provision, it is our view that, by dialing 911, the caller impliedly con­
sents to the disclosure of information regarding his location at the time of the
call. 12
  The whole purpose of a 911 call is to seek the aid of appropriate government
officials in responding to an emergency at a particular place. Typically, that emer­
gency is in the immediate vicinity of the caller— indeed, it often involves the
caller himself and thus his exact location— and the whole purpose of the call

    11 The legislative history o f § 1002(a) supports our conclusion. As explained in the House Report (there was no
Senate Report submitted with CALEA), Congress was acting to ensure that “ the authority for pen registers and
trap and trace devices cannot be used to obtain tracking or location information, other than that which can be deter­
mined from the phone num ber." H.R. Rep. No. 103-827, at 17 (1994), reprinted in 1994 U.S.C.C.A.N. 3489, 3497;
see also id. at 22, reprinted in 1994 U.S.C.C.A.N. at 3502 ( “ Call identifying information obtained pursuant to
pen register and trap and trace orders may not include information disclosing the physical location o f the subscriber
sending or receiving the message, except to the extent that location is indicated by the phone n um ber.") (emphasis
added). “ Currently, in some cellular systems, transactional data that could be obtained by a pen register may include
location information." Id. at 17, reprinted in 1994 U.S.C.C.A.N. at 3497 (emphasis added).
    12Although there appear to be no cases interpreting §2 7 0 3 ’s consent provision, and the legislative history of
the section is silent on the matter, some guidance can be found in analyses o f the consent provision in Title DI
o f the Omnibus Crime Control and Safe Streets Act o f 1968, 18 U.S.C. § 231 l(2)(c>. Section 2511(2)(c) provides
in part that “ [i]t shall not be unlawful under this chapter for a person acting under color o f law to intercept a
wire, oral, or electronic communication, where . . . one o f the parties to the communication has given prior consent
to such interception.’- According to the legislative history o f §251 l(2)(c), “ (c)onsent may be expressed or implied.”
S. Rep. No. 90-1097, at 94 (1968), reprinted in 1968 U.S.C.C.A.N. 2112, 2182 ( “ Surveillance devices in banks
or apartment houses for institutional or personal protection would be impliedly consented to .” ). “ In the Title in
milieu as in other settings, consent inheres where a person's behavior manifests acquiescence or a comparable vol­
untary diminution of his or her otherwise protected rights.” Criggs-Ryan v. Smith, 904 F.2d 112, 116 (1st Cir.
 1990) (citations omitted). “ fl]raplied consent— o r the absence o f it — may be deduced from ‘the circumstances
prevailing’ in a given situation. . . . The circumstances relevant to an implication of consent will vary from case
to case, but the compendium will ordinarily include language o r acts which tend to prove (or disprove) that a party
knows of, or assents to, encroachments on the routine expectation that conversations are private.” Id. at 117 (citation
omitted). See also United States v. Amen , 831 F.2d 373, 378-79 (2d Cir. 1987) (no violation o f Title DI where
taping o f prison inmates* telephone calls was impliedly consented to by inmates who used phones when on notice
o f the monitoring procedures at prison; “ [h]ere we imply consent in fact from surrounding circumstances indicating
that the appellants knowingly agreed to the surveillance” ) (citations omitted), cert, denied, 485 U.S. 1021 (1988).

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is to inform officials of that location in order for the caller to obtain, and the
emergency service officials to provide, help. The caller is the source of the loca­
tion information needed by the government to respond, and his call evidences
not merely an expectation, but in fact a purpose, of conveying that information
to the authorities. If the caller himself does not tell the authorities where he is
located (which he generally does), it is presumably due to the exigent cir­
cumstances resulting from the emergency, and not to any desire to withhold such
information. Even if the emergency is in a different location, his decision to reach
out to government officials to seek their help indicates that he would similarly
tell them his location if it would help them respond to the emergency.13 The
mere possibility that a caller subjectively does not wish his location to be revealed
would not negate the consent presumed from his making the 911 call.14

C. Wireless Carriers May Transmit to Public Safety Authorities Information
Regarding the Physical Location o f Cellular Callers Dialing 911 Without
Violating the Fourth Amendment

  1. There is no “ Search” Within the Meaning o f the Fourth Amendment Because
911 C allers H ave N o Actual o r Reasonable Expectation o f Privacy in Information
Regarding Their Location

   The Fourth Amendment protects individuals from “ unreasonable searches.”
U.S. Const, amend. IV. For the Fourth Amendment even to apply to a particular
government action, the person invoking its protection must be able to claim “ a
‘justifiable,’ a ‘reasonable,’ or a ‘legitimate expectation of privacy’ that has been

    13 C alling 911 and triggering the governm ent's emergency response invalidates any claim by a caller that he does
not in fact consent to the disclosure of information regarding his location. If he chooses to seek such emergency
aid, he implicitly consents both to aiding th e authorities in this limited way and to action taken by the government
to verify his call. See Nolan v. United States, 423 F.2d 1031, 1043 (10th Cir. 1969) (telephone company’s monitoring
o f calls does not violate 47 U.S.C. §605 because illegal user has impliedly consented to company's attempts to
properly bill user), cert, d e n ie d 400 U.S. 848 (1970); Bubis v. United States, 384 F.2d 643, 648 (9th Cir. 1967)
(*‘[w]hen a subscriber o f a telephone system uses the system 's facilities in a manner which reasonably justifies
the telephone com pany’s belief that he is violating his subscription rights, then he must be deemed to have consented
to the com pany’s m onitoring o f his calls to an extent reasonably necessary for the company’s investigation" and
there is no violation o f 47 U.S.C. §605); Commonwealth v. Gullett, 329 A.2d 513, 519 (Pa. 1974) (Party calling
police to report homicide, its location and num ber o f bodies has no claim for violation o f Pennsylvania W iretapping
and Electronic Surveillance Control Act, 18 Pa. C.S.A. §5703, where, “ [fjrom the nature o f the call, the non-
confidential quality o f the information conveyed, the emergency atmosphere the communication engendered, and
the particular agency to which the disclosure was directed, it is apparent that the caller did not intend the privacy
o f the com m unication to be maintained. Rather, the conclusion is inescapable that a call made under these cir­
cum stances carried with it the permission o f the caller to divulge the communication to authorized police personnel
other than the officer who happened to take the message and to use the communication to investigate the reported
crim e by any reasonable m eans.").
    14See United States v. Tzakis, 736 F.2d 867, 8 71-72 (2d Cir. 1984) (defendant cannot assert post-hoc limits
on a listener’s recording o f conversation by alleging that his willingness to allow overhearing did not encompass
perm ission to record); United States v. Jachimko, 19 F.3d 296, 299 (7th Cir. 1994) ( ‘‘where a suspect does not
withdraw his valid consent to a search for illegal substances before they are discovered, the consent remains valid");
Jones v. Berry, 722 F.2d 443, 449 (9th C ir. 1983) (consent search is valid where consent revoked after search
com plete), cert, denied, 466 U.S. 971 (1984).

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invaded by government action.” Smith v. M aryland, 442 U.S. 735 , 740 (1979)
(citations omitted). This inquiry embraces two discrete questions. The first is
“ whether the individual, by his conduct, has ‘exhibited an actual (subjective) ex­
pectation of privacy,’ ” — whether the individual “ has shown that ‘he seeks to
preserve [something] as private.’ ” Id. at 740 (quoting K atz v. United States, 389
U.S. 347, 361 (Harlan, J., concurring), 351 (1967)). The second question is
“ whether the individual’s subjective expectation of privacy is ‘one that society
is prepared to recognize as “ reasonable,” ’ ” — whether “ the individual’s expec­
tation, viewed objectively, is ‘justifiable’ under the circumstances.” Id. (quoting
Katz, 389 U.S. at 361 (Harlan, J., concurring), 353).
   In our opinion, a cellular caller dialing the 911 emergency line has not exhibited
an “ actual (subjective) expectation of privacy” in information regarding his phys­
ical location, much less a “ reasonable” one. It is hard to imagine any clearer
indication of the absence of an expectation of privacy than a cry for help; by
reaching out to government officials to seek their help, the caller indicates that
he has no expectation of privacy in information that could help the authorities
respond to the emergency.15
   Even assuming that, in some number of cases, the caller actually expects his
physical location to remain private, we believe that expectation is not “ one that
society is prepared to recognize as ‘reasonable.’ ” Katz, 389 U.S. at 361. A caller
dialing 911 seeking assistance cannot reasonably expect that information regarding
his location will remain private when public service organizations need such infor­
mation first and foremost to expeditiously provide the emergency assistance re­
quested by the caller, and secondly to ensure that the call is legitimate and thus
worthy of response.16
   In addition, the Supreme Court has repeatedly held that a person has no expecta­
tion of privacy in information he voluntarily turns over to third parties.17 In order
to complete his call, the cellular caller must convey his signal and its cor­
responding cell site location to the carrier. The caller therefore has no reasonable

    13 Although no court has directly addressed this issue, our conclusion is supported by cases holding that a person
calling 911 has no expectation o f privacy in the contents o f his call. “ There is no expectation o f privacy when
a person makes a 911 call. Instead, there is an expectation that the information provided will be recorded and dis­
closed to the public.” State ex rel. Cincinnati Enquirer v. Hamilton County, Ohio, 662 N.E.2d 334, 337 (O hio
1996) (tape recordings o f 911 calls are public records that are not exempt from disclosure and must be immediately
released upon request); see also State v. Cain, 613 A.2d 804, 809 (Conn. 1992) (tape recordings o f 911 calls are
public records); -Sra/e v. G ray, 741 S.W.2d 35, 38 (Mo. App. 1987) (same).
    ieSee United States v. Van Poyck, 77 F.3d 285, 290-91 (9th Cir.) (prisoner has no reasonable expectation of
privacy in outbound calls), cert, denied , 519 U.S. 912 (1996); People v. Suite, 161 Cal. Rptr. 825, 829 (Cal. App.
1980) (person telephoning police and threatening to bomb public building “ cannot reasonably expect that records
o f the call will be private; the only reasonable expectation under such circumstances is that police will make use
o f every available technology to trace the source o f that call” ).
    17 “ [T]he Fourth Amendment does not prohibit the obtaining o f information revealed to a third party and conveyed
by him to Government authorities, even if the information is revealed on the assumption that it will be used only
for a limited purpose and the confidence placed in the third party will not be betrayed.” United States v. Miller,
425 U.S. 435, 443 (1976) (bank depositor has no legitimate expectation o f privacy in financial information voluntarily
conveyed to banks and exposed to their employees in the ordinary course o f business); see also Smith, 442 U.S.
at 744 (telephone caller has no reasonable expectation o f privacy in phone number voluntarily dialed).

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expectation of privacy with regard to that information, which is exactly the loca­
tion information that will be disclosed in phase one of the new FCC rule. And
it is the strength of this same signal — information voluntarily turned over by the
caller to a third party— that would be measured from different antennas and cell
sites, and then analyzed in phase two in order more precisely to determine his
location. An expectation of privacy simply is not “justified” in these cir­
cumstances.
   In sum, because a cellular caller dialing 911 has no actual or reasonable expecta­
tion of privacy as to information regarding his physical location, there will be
no “ search” within the meaning of the Fourth Amendment, and thus no con­
straints imposed by the Fourth Amendment, when wireless carriers transmit such
information to public safety authorities.

   2. C ellular C allers Dialing 911 Have Impliedly Consented to the Transmission
o f Information Regarding Their Physical Location

   Even assuming that the provision to public safety agencies of information re­
garding the physical location of a cellular caller dialing 911 would constitute a
search within the meaning of the Fourth Amendment, that search would be lawful
if the caller consented to it, as consent is “ one of the specifically established
exceptions to the requirements of both a warrant and probable cause.” Schneckloth
v. Bustam onte, 412 U.S. 218, 219 (1973). As set forth above, we believe that
dialing 911 evidences such consent.
   Consent to a warrantless search can be explicit or can be implied from conduct.
The Seventh Circuit recently reviewed the caselaw on implied consent, summa­
rizing the pertinent analysis as follows:

          Generally, in deciding whether to uphold a warrantless search on
          the basis of implied consent, courts consider whether (1) the person
          searched was on notice that undertaking certain conduct, like at­
          tempting to enter a building or board an airplane, would subject
          him to a search, (2) the person voluntarily engaged in the specified
          conduct, (3) the search was justified by a ‘vital interest’, (4) the
          search was reasonably effective in securing the interests at stake,
          (5) the search was only as intrusive as necessary to further the inter­
          ests justifying the search and (6) the search curtailed, to some ex­
          tent, unbridled discretion in the searching officers.

M cGann v. N ortheast III. Regional Commuter R.R., 8 F.3d 1174, 1181 (7th Cir.
1993) (citations omitted).18
   18 44W e decline to regard these six factors as dispositive criteria. Rather, these factors should be examined carefully
in each case in evaluating the totality o f the circumstances and in respecting the consideration that the courts not
unnecessarily extend exceptions to the warrant requirem ent." Id. at 1181. See also Almeida-Sanchez v. United States,

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   Applying this analysis to the “ search” here at issue leads us to conclude that
a person using his cellular telephone to call 911 impliedly consents to the carrier
providing public safety officials with information as to his physical location. Al­
most all, if not all, of the above-enumerated factors will be satisfied. The caller
will have voluntarily called 911; the search will be justified by a vital interest
in responding to an emergency and should be quite effective in facilitating that
response; and the search will be limited to determining the caller’s physical loca­
tion, and thus will be only as intrusive as necessary to respond quickly and effi­
ciently to the emergency and should minimize any risk of unbridled discretion
by officers. The only factor possibly raising a question would be the first. In
most instances, a person calling 911 will be doing so to obtain help for himself
or someone in his immediate vicinity, and thus he will undoubtedly be “ on no­
tice” that calling 911 will entail disclosure of his location. Even if the caller
is seeking help for a third party in a different location, he should be deemed
to be on notice that his call will entail disclosure of his physical location in order
to expedite the government’s response.19 Moreover, this simply is not a situation
with any of the indicia of unwarranted interference into the private aspects of
a person’s life. In particular, the government’s “ search” is in response to the
caller’s request for assistance; it is not a government-initiated intrusion into a per­
son’s private life.

                                                                      RICHARD L. SHEFFRIN
                                                                D eputy Assistant Attorney General
                                                                     Office o f Legal Counsel

413 U.S. 266, 271 (1973) (warrantless inspections are constitutional where businessmen engaged in federally regu-
lated enterprises “ accept the burdens as well as the benefits o f their trade . . . [and] in effect consent! ] to the
restrictions placed upon [them ]” ); United States v. Bonanno , 487 F.2d 654, 658-59 (2d Cir. 1973) (consent shown
where “ informer went ahead with a call after knowing what the law enforcement officers were about” ).
   19 Although we think it unnecessary, the FCC could consider publishing a notice in the telephone book and/or
in the standard service contract signed by each subscriber that anyone calling 911 will be deem ed to consent to
disclosure of their physical location.

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