FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 06-30582
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-04-30057-ALA
STEPHEN WAYNE MURPHY,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
                for the District of Oregon
         Ann L. Aiken, District Judge, Presiding

                  Argued and Submitted
             July 12, 2007—Portland, Oregon

                  Filed February 20, 2008

    Before: Alfred T. Goodwin, Stephen Reinhardt, and
            Milan D. Smith, Jr., Circuit Judges.

                Opinion by Judge Reinhardt




                           1519
1522              UNITED STATES v. MURPHY


                        COUNSEL

Vance M. Waliser, Medford, Oregon, for the defendant-
appellant.

Karin J. Immergut, United States Attorney, District of Ore-
gon, Judith R. Harper, Special Assistant United States Attor-
ney, Medford, Oregon, for the plaintiff-appellee.
                   UNITED STATES v. MURPHY                  1523
                          OPINION

REINHARDT, Circuit Judge:

   Defendant Murphy appeals the district court’s denial of his
motion to suppress evidence seized as a result of two
searches. We conclude that one search was lawful and one
was not. The first search, a protective sweep of storage units
following Murphy’s arrest, was justified by the officer’s legit-
imate concern about the potential presence of confederates in
the area. We conclude that the district court’s ruling as to this
search was correct. The second search occurred two hours
later, after Murphy, who was residing in the units temporarily,
had refused to consent but the officers subsequently obtained
consent from the individual who rented the storage units. In
light of the Supreme Court’s recent decision in Georgia v.
Randolph, 

(2006), we reverse the district court’s
denial of the suppression motion as to this search.

                               I.

   On August 4, 2004, officers from the Jackson County Nar-
cotics Enforcement Team followed two individuals, Cozo and
Wyman, who were observed purchasing precursor ingredients
used to manufacture methamphetamine, to a storage facility.
The officers knew that defendant Murphy was staying in stor-
age units rented by Dennis Roper at this facility. They inter-
cepted Wyman as he was driving away from the facility and
he told them that Cozo was still inside unit 17. The officers
waited outside until Cozo left the unit. Officer Thompson then
knocked on the door and Murphy opened it holding a ten-inch
piece of metal pipe. Thompson recognized Murphy and knew
him to be a methamphetamine manufacturer. Thompson asked
Murphy to drop the pipe, but he did not initially comply.
Thompson then stepped to the right and asked again; this time
Murphy dropped the pipe. From his position, Thompson was
able to observe in plain view an operating methamphetamine
lab inside the storage unit. As a result, he arrested Murphy.
1524              UNITED STATES v. MURPHY
Murphy refused to give his consent to a search of the units,
so Thompson performed a short protective sweep of units 17
and 18. Murphy was transported to jail and Thompson left the
scene to prepare an affidavit for a search warrant.

   Later that afternoon, Roper arrived at the scene and police
arrested him on outstanding warrants. Roper claimed that he
had no knowledge of the methamphetamine lab but that he
had given Murphy permission to reside at the facility. He then
consented in writing to a search of the units. The officers
seized the methamphetamine lab as a result of this search.

   Murphy challenged the protective sweep and the validity of
Roper’s consent to the subsequent search of the units. The
district court denied his motion to suppress and Murphy
entered a conditional plea of guilty, reserving his right to
appeal the denial of the motion. In March 2006, the Supreme
Court held in Georgia v. Randolph, 

(2006), that
a warrantless entry and search is invalid when one occupant
refuses permission to search even though another occupant
with authority consents. 

Murphy filed a motion
to reconsider in light of Randolph, which the district court
denied. Murphy was sentenced to 120 months imprisonment.
He now appeals the district court’s denial of his motion to
suppress the evidence seized in the storage unit.

                             II.

   [1] Both of the searches that Murphy challenges were con-
ducted without a warrant. Warrantless searches are unconsti-
tutional unless the government demonstrates that they “fall
within certain established and well-defined exceptions to the
warrant clause.” United States v. Delgadillo-Velasquez, 

, 1298 (9th Cir. 1988) (quoting United States v. Per-
domo, 

, 918 (9th Cir. 1986)).

  [2] One exception to the warrant clause is a protective
sweep. A valid protective sweep must be supported by “ ‘spe-
                      UNITED STATES v. MURPHY                        1525
cific and articulable facts supporting [the] belief that other
dangerous persons may be in the building or elsewhere on the
premises.’ ” 

States v. Whitten, 

, 1014 (9th Cir. 1983)). The district court held that the
protective sweep was valid because “defendant was holding
a metal pipe.” Murphy argues that this is not enough to justify
a protective sweep, and we agree. The purpose of a protective
sweep is to protect law enforcement officers from attack by
dangerous confederates. See Maryland v. Buie, 

,
333-34 (1990). Thus, the government must articulate facts
that could have led the officer to the conclusion that there
might be another person hiding inside the storage unit. The
fact that Murphy opened the door holding a metal pipe is
irrelevant to that question. Thus, the district court erred in
upholding the protective sweep for the reason that it did. We
may, however, affirm the district court’s decision on any
ground supported by the record. See Atel Fin. Corp. v. Quaker
Coal Co., 

, 926 (9th Cir. 2003) (citing Cigna
Prop. & Cas. Ins. Co. v. Polaris Pictures Corp., 

, 418 (9th Cir. 1998)).

   [3] Although we do not believe that the district court’s
rationale for upholding the protective sweep was valid, we
conclude that there is evidence in the record to support the
search. Officer Thompson testified that he conducted the pro-
tective sweep because Roper, who he knew rented the storage
unit, and for whom there was an outstanding arrest warrant,
was not accounted for at the time. He testified that he was
“looking for a body to make sure there was [sic] no other peo-
ple in there.” Because Thompson was aware of the possibility
that Roper might be inside the storage unit and limited his
protective sweep to the immediate area, we conclude that the
government has met its burden of demonstrating that the
sweep was valid.1
  1
    It is not apparent from the record whether any evidence was seized dur-
ing the protective sweep. We do not consider here the validity of any such
seizure. We consider only the validity of the protective sweep itself.
1526               UNITED STATES v. MURPHY
                              III.

   The second search was conducted after Murphy had refused
to consent to a search, and had been arrested and removed
from the scene. Officers then obtained consent from Roper
two hours after Murphy had expressly refused to grant his.

   [4] The district court incorrectly held that because the offi-
cer had already viewed the methamphetamine lab in plain
view during the protective sweep, the subsequent search was
lawful. First, the plain view doctrine is not an exception to the
warrant requirement. We have recognized that “even [when]
contraband plainly can be seen and identified from outside the
premises, a warrantless entry into those premises to seize the
contraband would not be justified absent exigent circum-
stances.” G & G Jewelry, Inc. v. City of Oakland, 

, 1101 (9th Cir. 1993); see also Horton v. California, 

, 137 & n.7 (1990). Second, a warrantless search of
the premises, such as a protective sweep, must be “ ‘strictly
circumscribed by the exigencies which justify its initiation.’ ”
Mincey v. Arizona, 

, 393 (1978) (quoting Terry
v. Ohio, 

, 25-26 (1968)). Under Mincey, once the
exigencies of the initial entry have dissipated, the police must
obtain a warrant for any further search of the premises. 

Thus, as soon as Thompson completed his protective
sweep of the storage unit and departed, the exigency that jus-
tified that warrantless search ended. Neither the government
nor the district court cites any further exigency that would
have justified the second search two hours after the protective
sweep was completed. Presumably, even the officer under-
stood that he could not conduct further searches or seizures in
the storage unit because he left the scene to obtain a warrant.
The district court erred in relying on the plain view doctrine
to justify a warrantless search when exigent circumstances did
not exist.

  [5] The government contends further that the second search
was independently justified by Roper’s grant of his voluntary
                      UNITED STATES v. MURPHY                        1527
consent.2 Murphy argues, however, that under Georgia v.
Randolph, 

(2006), Roper’s consent to the sec-
ond search did not overcome his earlier objection to it. In
Randolph, police were called to a residence after a domestic
dispute. 

There, Mrs. Randolph told the officer that
her husband was a drug user and that there was evidence to
support her accusation in the house. 

asked Mr.
Randolph for permission to search the house and he refused.

Randolph consented to a search of the resi-
dence and the officer entered and seized evidence of Mr. Ran-
dolph’s drug use. 

Court held that “a
warrantless search of a shared dwelling for evidence over the
express refusal of consent by a physically present resident
cannot be justified as reasonable as to him on the basis of con-
sent given to the police by another resident.” 

   The government attempts to distinguish the present case
from Randolph in two ways. First, Randolph involved co-
tenants of a residence who both clearly had the authority to
consent or refuse to consent to a search. This case involves a
storage unit, which Murphy did not own or pay rent for and
thus, the government contends, he did not have the authority
to agree or object to a search. Second, in Randolph both the
consenting tenant and the refusing tenant were present at the
scene and gave contemporaneous conflicting responses to the
officers, whereas Murphy refused to consent before he was
arrested and removed from the scene, and Roper consented
two hours later when Murphy was no longer present. Because
we conclude that neither distinction is legally meaningful and
that the rationale in Randolph applies to the facts of this case,
we hold that the second search violated Murphy’s Fourth
  2
    Roper did not reside in the units but he stored his business equipment
in them and entered and left at will. Thus, Roper is in between a landlord,
who may not consent to a search, see Chapman v. United States, 

, 616-17 (1961), and a co-tenant, who may. We will assume for the
purposes of this opinion, however, that he has the same rights as a co-
tenant.
1528               UNITED STATES v. MURPHY
Amendment rights, even though both Roper and Murphy had
the authority to grant or withhold consent.

   [6] It is well established that a person with common author-
ity over property can consent to a search of that property
without the permission of the other persons with whom he
shares that authority. See Illinois v. Rodriguez, 

(1990); United States v. Matlock, 

(1974). Com-
mon authority “does not rest upon the law of property, with
its attendant historical and legal refinements.” 

n. 7. Rather, it is established through “mutual use
of the property by persons generally having joint access or
control for most purposes.” 

the Supreme
Court has found that two people sharing a duffel bag have
common authority over the bag and one of them may consent
to a search of the bag — even if the evidence sought or seized
implicates the other in a crime. See Frazier v. Cupp, 

, 740 (1969). By contrast, an individual lacks common
authority and may not consent to a search if that person occa-
sionally spends the night at an apartment but does not enter-
tain guests there, does not spend time in the apartment when
the actual occupant is not present, does not contribute to the
rent, and does not, to the knowledge of the occupant, possess
a key. 

(finding the search legiti-
mate because even though the person who stayed in the apart-
ment occasionally did not have actual authority, the police
reasonably believed that she did).

   [7] Despite some testimony to the contrary, we conclude
that the evidence presented at the suppression hearing sup-
ports the district court’s determination that Murphy exercised
sufficient control over the storage units to possess the author-
ity to grant or withhold consent to a search of them. In short,
the district court held that Murphy had an expectation of pri-
vacy in the storage units, and we agree. At the hearing, Roper
testified that he allowed Murphy to stay in the storage units
beginning in early June and gave him a key that opened all of
the units. He also testified that he asked Murphy to leave in
                    UNITED STATES v. MURPHY                  1529
early July and requested that he return the key at that time. At
the time of the arrest, however, Roper told the officer who
arrested him that he allowed Murphy to stay in the unit, but,
the district court found, did not tell him that he had asked
Murphy to leave. Murphy, too, testified that Roper did not ask
him to leave and that Roper had in fact visited him at the stor-
age unit on the evening preceding the events in question, thus
indicating his tacit consent to Murphy’s continued presence.
Given all of this contradictory evidence, the district court’s
ruling that Roper’s testimony that he asked Murphy to leave
lacked credibility was not clearly erroneous. Accordingly, we
find no basis for reversing the district court’s determination
that Murphy lived in unit 14 with Roper’s permission.

   Moreover, although the district court was less certain about
the issue of unit 17, Murphy stored personal belongings in
that unit — the unit in which the majority of the evidence that
supports the underlying conviction was found. Testimony at
the hearing revealed that the officers found Murphy’s per-
sonal belongings in unit 17, including his personal papers, as
well as a cordless phone whose base was located in unit 14.
Additionally, it is clear that Murphy stored the materials and
equipment that were seized and formed the basis of his con-
viction in unit 17. He also invited guests into the unit, which
the officers observed when they followed the individuals who
bought methamphetamine precursor ingredients to the storage
facility. Possession of a key, storage of personal belongings,
and the ability to entertain guests are all factors that establish
Murphy’s common authority over unit 17. They reflect that
Murphy enjoyed “joint access or control for most purposes.”

n.7; see also 

.

  [8] Nevertheless, the government argues that Murphy did
not have the authority to object to the search because he did
not pay rent. There is no requirement in Randolph, or the
cases that preceded it, that an occupant pay rent in order to
possess the authority to object to a search of property in
1530                  UNITED STATES v. MURPHY
which he resides, temporarily or otherwise. Quite the oppo-
site. The Randolph Court acknowledged the “multiplicity of
living arrangements” that people have, but stated that such
variance does not mean that “the rule to be applied to them
is similarly varied.” 

n.2. Addition-
ally, Randolph reiterated the long-established understanding
that common authority for the purposes of the Fourth Amend-
ment is not equivalent to technical property rights. 

Indeed, “[t]he common authority that counts under the Fourth
Amendment may thus be broader than the rights accorded by
property law.” Id. (citing 

). The
important question is not who possesses a property right, but
rather what are the dictates of “widely shared social expecta-
tions.” 

As explained above, Murphy was living in
one unit and kept his personal belongings in another, and thus
had a legitimate expectation of privacy in both units, regard-
less of whether he paid rent. The Supreme Court has held that
“overnight houseguests have a legitimate expectation of pri-
vacy in their temporary quarters because ‘it is unlikely that
[the host] will admit someone who wants to see or meet with
the guest over the objection of the guest.’ ” 

(quoting
Minnesota v. Olson, 

, 99 (1990)). By definition
house guests do not pay rent, and yet they have the authority
to refuse consent to a search. It is apparent, therefore, that
Roper’s temporary residence in the units entitled him to exer-
cise common authority over his living quarters.3

   [9] Relatedly, the government argues that Roper’s consent
trumped Murphy’s refusal because Roper had greater author-
ity over the premises since he paid the rent and stored his
medical equipment there. Again, although there may be a
basis in property law for this argument, “neither state-law
property rights, nor common contractual arrangements” gov-
ern the protection of the Fourth Amendment. 

  3
  We note, incidentally, that even if the payment of rent were a require-
ment, Murphy would qualify because his arrangement with Roper, that he
would work in exchange for staying in the storage unit, would suffice.
                    UNITED STATES v. MURPHY                  1531
According to the Randolph Court, “[u]nless the people living
together fall within some recognized hierarchy, like a house-
hold of parent and child or barracks housing military person-
nel of different grades, there is no societal understanding of
superior and inferior.” 

There is no basis for the
government’s contention that the validity of consent or refusal
to search hinges on ownership or level of authority over the
property.

   [10] Next, the government argues that Randolph does not
apply because the storage unit was not a residence. As an ini-
tial matter, Murphy’s living situation was unconventional, but
the record shows that the storage units were the closest thing
that he had to a residence. He was sleeping in unit 14 and
storing his belongings in unit 17. For the purposes of the
Fourth Amendment, this is sufficient to create an expectation
of privacy and thus the authority to refuse a search. Moreover,
even if the storage units could not be considered a residence,
there is no reason that the rule in Randolph should be limited
to residences. Randolph is rooted in the idea of common
authority and the Supreme Court has extended the principle of
common authority well beyond residences. In Frazier v.
Cupp, 

(1969), the Court held that the shared use
of a duffel bag was enough to give rise to common authority
between users such that either user could give lawful consent
to a search. 

Certainly, business offices are also sub-
ject to the protection of the Fourth Amendment. See Mancusi
v. DeForte, 

, 369 (1968). Thus, we hold that
Murphy had common authority over the storage units and
could legitimately consent or refuse to give consent to a
search of those units.

   [11] The second major distinction that the government
attempts to make between this case and Randolph is that in
the former, unlike in the latter, the objecting co-tenant was not
physically present when the other tenant gave consent to the
search. Here, Murphy refused consent and was subsequently
arrested and removed from the scene. Two hours later, offi-
1532                 UNITED STATES v. MURPHY
cers located Roper and obtained consent from him to search
the units. Roper did not know that Murphy had previously
refused consent and Murphy was not present to object once
again to the second search. We see no reason, however, why
Murphy’s arrest should vitiate the objection he had already
registered to the search. We hold that when a co-tenant
objects to a search and another party with common authority
subsequently gives consent to that search in the absence of the
first co-tenant the search is invalid as to the objecting co-
tenant.

   [12] We find support for our holding in the Randolph
Court’s treatment of the related issue of police removal of a
tenant from the scene for the purpose of preventing him from
objecting to a 

. The Court held that
third party consent to a search is valid only “[s]o long as there
is no evidence that the police have removed the potentially
objecting tenant from the entrance for the sake of avoiding a
possible objection.” 

police cannot prevent a co-
tenant from objecting to a search through arrest, surely they
cannot arrest a co-tenant and then seek to ignore an objection
he has already made. Nor, more generally, do we see any rea-
son to limit the Randolph rule to an objecting tenant’s
removal by police. Once a co-tenant has registered his objec-
tion, his refusal to grant consent remains effective barring
some objective manifestation that he has changed his position
and no longer objects. The rule that Randolph establishes is
that when one co-tenant objects and the other consents, a
valid search may occur only with respect to the consenting
tenant. It is true that the consent of either co-tenant may be
sufficient in the absence of an objection by the other, either
because he simply fails to object or because he is not present
to do so. Nevertheless, when an objection has been made by
either tenant prior to the officers’ entry, the search is not valid
as to him and no evidence seized may be used against him.4
  4
   Refusing to grant consent and objecting to the search are one and the
same for Fourth Amendment purposes. The terms are used interchange-
ably throughout this opinion, as they are in Randolph.
                   UNITED STATES v. MURPHY                 1533
Rather, as in this case, in the absence of exigent circum-
stances, the police must obtain a warrant before conducting
the search.

                              IV.

  For the foregoing reasons, we hold that the first search was
a valid protective sweep. We do not rule, however, on the
validity of the seizure of any evidence obtained during that
search. We further hold that the second search violated Mur-
phy’s Fourth Amendment rights and we reverse the district
court’s ruling regarding the evidence seized as a result of that
search. The decision of the district court is therefore

  AFFIRMED in part and REVERSED in part.