                       FOR PUBLICATION

    UNITED STATES COURT OF APPEALS
         FOR THE NINTH CIRCUIT


UNITED STATES OF AMERICA,                      No. 14-50549
          Plaintiff-Appellee,
                                                D.C. No.
                  v.                      3:13-cr-03921-BEN-1

MICHAEL LUSTIG, AKA
George,                                          OPINION
        Defendant-Appellant.


        Appeal from the United States District Court
           for the Southern District of California
         Roger T. Benitez, District Judge, Presiding

            Argued and Submitted January 8, 2016
                    Pasadena, California

                        Filed July 29, 2016

Before: Paul J. Watford and Michelle T. Friedland, Circuit
  Judges and J. Frederick Motz,* Senior District Judge.

                 Opinion by Judge Friedland;
                Concurrence by Judge Watford




 *
   The Honorable J. Frederick Motz, Senior District Judge for the U.S.
District Court for the District of Maryland, sitting by designation.
2                   UNITED STATES V. LUSTIG

                           SUMMARY**


                           Criminal Law

    The panel affirmed the district court in part, reversed in
part, and remanded, in a case in which an officer conducted
warrantless searches, incident to arrest, of cell phones found
in the defendant’s pockets two years before the Supreme
Court held that the Fourth Amendment requires law
enforcement officers to obtain a warrant before they may
search an arrestee’s cell phone.

    The panel held that binding precedent at the time of the
searches provided a reasonable basis to believe the searches
were constitutional, and that the good-faith exception to the
exclusionary rule therefore applies to the evidence obtained
from those searches. The panel disagreed with the
defendant’s contention that the delay between the initial
searches and more comprehensive stationhouse searches
undertaken four days later rendered the stationhouse searches
unconstitutional.

    Rejecting the defendant’s contention that harmless error
review does not apply in the context of a Fed. R. Crim. P.
11(a)(2) conditional guilty plea, the panel held that harmless
error review applies to the district court’s concededly
erroneous failure to suppress the fruit of searches of other cell
phones found in the defendant’s car. The panel held that the
standard that governs harmless error review in Rule 11(a)(2)
appeals is whether the government has proved beyond a

  **
     This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
                 UNITED STATES V. LUSTIG                    3

reasonable doubt that the erroneously denied suppression
motion did not contribute to the defendant’s decision to plead
guilty. The panel concluded that the government did not
meet its burden of establishing harmless error, and remanded
to allow the defendant to the opportunity to withdraw his
guilty plea.

    Concurring, Judge Watford wrote that he does not think
Rule 11(a)(2)—or basic principles of contract law governing
plea agreements—permits any harmless error inquiry in this
context. He wrote that if this court does anything other than
affirm in full the denial of the defendant’s suppression
motion, he is entitled to withdraw his guilty plea without
more.


                        COUNSEL

Timothy A. Scott (argued) and Nicolas O. Jimenez, Coleman,
Balogh & Scott LLP, San Diego, California, for Defendant-
Appellant.

Helen H. Hong (argued), Assistant United States Attorney;
Peter Ko, Chief, Appellate Section, Criminal Division; Laura
E. Duffy, United States Attorney; United States Attorney’s
Office, San Diego, California; for Plaintiff-Appellee.
4                   UNITED STATES V. LUSTIG

                             OPINION

FRIEDLAND, Circuit Judge:

    The United States Supreme Court held in Riley v.
California, 134 S. Ct. 2473 (2014), that the Fourth
Amendment requires law enforcement officers to obtain a
warrant before they may search an arrestee’s cell phone.
Approximately two years before that decision, an officer
arresting Michael Lustig conducted warrantless searches,
incident to the arrest, of cell phones found in Lustig’s
pockets. We must determine whether pre-Riley precedent
provided a reasonable basis to believe such searches were
constitutional. Because we hold that binding appellate
precedent at the time of the searches did provide a reasonable
basis to believe the searches were constitutional, the good-
faith exception to the exclusionary rule applies to the
evidence obtained from those searches. In addition, we must
determine the effect of a concededly erroneous denial of a
motion to suppress evidence obtained from separate searches
of other cell phones found in Lustig’s car. To do so, we first
adopt our sister circuits’ test for evaluating harmlessness in
the context of a conditional guilty plea. Because the
Government has not met its burden of establishing
harmlessness under that test, Lustig must be given an
opportunity to vacate his guilty plea if he so wishes. We thus
affirm in part, reverse in part, and remand.1




 1
   In a concurrently filed memorandum disposition, we address and reject
several secondary arguments Lustig raises in his briefing.
                  UNITED STATES V. LUSTIG                      5

                               I

    In June 2012, a task force consisting of local and federal
law enforcement agencies conducted a sting operation to
obtain evidence of prostitution offenses. To effectuate the
operation, an undercover officer posed as a prostitute and
placed listings on a classified advertisements website.
Defendant-Appellant Michael Lustig responded to the
advertisements and agreed to meet the undercover officer at
a hotel in Encinitas, California. Lustig was arrested at the
hotel for soliciting prostitution in violation of California law.
Upon the arrest, Deputy Sheriff Chase Chiappino seized and
searched cell phones found on Lustig’s person and in his car.

    Two cell phones were seized from Lustig’s pockets
incident to his arrest (the “Pocket Phones”). One was an
Apple iPhone, which Chiappino, upon its seizure, unlocked
by swiping across the screen. Chiappino observed that the
phone opened to the website where the fake advertisement
was posted, and he located the phone’s number on its settings
page. The other Pocket Phone was a Kyocera flip phone.
Chiappino searched the Kyocera phone by viewing its call
history and text messages and identifying its phone number.
The search revealed text messages suggesting further
involvement with prostitution.

   Officers seized additional cell phones from Lustig’s car,
which was in the parking lot of the hotel (the “Car Phones”).
At the scene, Chiappino searched those phones and found
additional text messages regarding prostitution.

    Four days later, Chiappino returned to searching the
phones. He downloaded content from the phones and
searched the phones’ contacts in law enforcement databases.
6                UNITED STATES V. LUSTIG

The parties dispute whether Chiappino searched the Car
Phones or the Pocket Phones first, and whether evidence
discovered in one set of phones motivated searches of the
other.

    In one of the Car Phones, Chiappino found text message
exchanges suggesting prostitution activity with a contact
named “Dominick.” He searched that contact’s phone
number in law enforcement databases but found no match.
He also found a contact named “Dominick” in one of the
Pocket Phones (the iPhone), searched that phone number, and
discovered a match to a twelve-year-old minor female, whom
the officers thereafter referred to as “MF1.”

    In his investigation of the Kyocera Pocket Phone,
Chiappino found a series of messages discussing libraries and
bookstores with a contact named “Andrew.” He searched for
that contact’s phone number in law enforcement databases
and matched it to a fourteen-year-old minor female, “MF2.”

    Officers then located and interviewed MF1 and MF2
separately, and both confirmed that they had engaged in
commercial sex activity with Lustig. According to a
declaration filed by Chiappino but disputed by Lustig, MF2
also directed officers to a motel, where the officers eventually
obtained video surveillance of Lustig entering and leaving a
room with a female whom officers identified as MF1.

    No warrants were obtained prior to any of these cell
phone searches. Sixteen months later, however, the officers
did obtain warrants to search two of the already searched Car
Phones.
                     UNITED STATES V. LUSTIG                              7

    Lustig was indicted in the United States District Court for
the Southern District of California on two counts of child sex
trafficking in violation of 18 U.S.C. §§ 1591(a) and (b), based
on his conduct with MF1 and MF2. During pretrial
proceedings, Lustig moved to suppress the evidence found
through the searches of the phones. He argued that the
seizure of the Car Phones, and the searches of both the Car
Phones and Pocket Phones, violated the Fourth Amendment.2
The district court, after declining to hold a hearing, denied the
motion approximately three months before the Supreme
Court issued its decision in Riley v. California, 134 S. Ct.
2473 (2014).

    Regarding the Pocket Phones, the district court held that
the searches were unconstitutional. It reasoned that
“searching an arrestee’s phone [without a warrant], beyond
what is in plain view, is an unreasonable search under the
Fourth Amendment . . . where the crime charged is a
misdemeanor,” as Lustig’s charge was at the time of arrest.3
Nevertheless, the district court went on to conclude that the
evidence found in the searches was admissible pursuant to the
good-faith exception to the exclusionary rule. The court
explained that at the time of the searches, the California
Supreme Court in People v. Diaz, 244 P.3d 501 (Cal. 2011),
had held that warrantless searches of cell phones seized from
an arrestee’s person incident to arrest did not violate the
Fourth Amendment. The district court also noted that there


 2
   Lustig conceded that the Pocket Phones were properly seized incident
to arrest.
  3
   Lustig was initially arrested for soliciting prostitution in violation of
California Penal Code § 647(b). The state charge against Lustig was
eventually dismissed.
8                UNITED STATES V. LUSTIG

were “no binding decisions to the contrary from the federal
courts.”

    As to the Car Phones, the district court held that they were
constitutionally seized, but that the warrantless searches of
the phones’ content were unconstitutional. The district court
nevertheless declined to suppress evidence obtained from the
Car Phones.        Because the Government eventually
attained—16 months later—a search warrant for the Car
Phones, the district court reasoned that the evidence would
inevitably have been discovered.

    Lustig filed two motions to reconsider these suppression
rulings, each of which the district court denied. Lustig
subsequently entered a conditional guilty plea pursuant to
Federal Rule of Criminal Procedure 11(a)(2). Under the plea
agreement, Lustig pled guilty to three counts of violating
18 U.S.C. § 1952(a)(3) by using a cell phone to facilitate a
prostitution offense under 18 U.S.C. § 1591, involving only
MF2, rather than the original indictment’s two counts for
child sex trafficking involving both MF1 and MF2. The
conditional guilty plea preserved Lustig’s right to appeal the
Fourth Amendment issues related to his motions to suppress.

     After the plea was entered, the Government filed as part
of its sentencing submissions the aforementioned declaration
from Chiappino, which asserted that evidence concerning
MF2 “was wholly untainted by” evidence from the Car
Phones, and that officers “would have inevitably discovered”
MF1 even if not for the Car Phone searches.

    Lustig now appeals the denial of his suppression motions.
                 UNITED STATES V. LUSTIG                     9

                              II

    We review a district court’s denial of a motion to suppress
evidence de novo. United States v. Fowlkes, 804 F.3d 954,
960 (9th Cir. 2015). We review a district court’s factual
findings for clear error and its application of the good-faith
exception de novo. United States v. Camou, 773 F.3d 932,
937 (9th Cir. 2014).

                             III

    Lustig advances two primary contentions on appeal.
First, he argues that pre-Riley authority provided no
reasonable basis for Chiappino to search without a warrant
the contents of the Pocket Phones, and that the district court
therefore erred in holding that the fruit of those searches was
admissible under the good-faith exception to the exclusionary
rule. Second, Lustig argues that the district court erred in
declining to suppress the Car Phone evidence. On appeal, the
Government concedes that the district court erred as to the
Car Phone evidence, but argues that the error was harmless
because it did not affect Lustig’s counts of conviction. We
address each issue in turn.

                              A

    In Riley v. California, 134 S. Ct. 2473 (2014), the
Supreme Court unanimously held that warrantless searches of
cell phones seized incident to arrest violate the Fourth
Amendment. Id. at 2495. There is thus no question that the
searches of Lustig’s Pocket Phones were unconstitutional.
The question on appeal is instead whether the good-faith
exception to the exclusionary rule nevertheless makes
10               UNITED STATES V. LUSTIG

admissible the evidence found in the Pocket Phone searches.
We hold that it does.

     The Fourth Amendment protects the “right of the people
to be secure in their persons, houses, papers, and effects,
against unreasonable searches and seizures.” U.S. Const.
amend. IV. To deter Fourth Amendment violations, courts
apply the exclusionary rule to suppress evidence that has been
unconstitutionally obtained. Davis v. United States, 564 U.S.
229, 236–37 (2011). In circumstances in which “suppression
fails to yield ‘appreciable deterrence,’” however, the Supreme
Court has held that “exclusion is ‘clearly . . . unwarranted.’”
Id. at 237 (alteration in original) (quoting United States v.
Janis, 428 U.S. 433, 454 (1976)). “[W]hen the police act
with an objectively ‘reasonable good-faith belief’ that their
conduct is lawful . . . the ‘deterrence rationale loses much of
its force,’” and therefore the exclusionary rule does not apply.
Id. at 238 (quoting United States v. Leon, 468 U.S. 897, 909,
919 (1984)). In Davis, the Supreme Court held that such a
“reasonable good-faith belief” exists when searches are
conducted “in objectively reasonable reliance on binding
appellate precedent.” Id. at 238, 249–50.

    Davis involved a vehicle search during which the arrestee,
Davis, was out of reaching distance of the car. Davis moved
to suppress a revolver found inside the vehicle. Id. at 223–36.
The Eleventh Circuit had long approved of such searches,
understanding the Supreme Court’s decision in New York v.
Belton, 453 U.S. 454 (1981), “to establish a bright-line rule
authorizing substantially contemporaneous” automobile
searches incident to arrest. Davis, 564 U.S. at 235 (citing
United States v. Gonzalez, 71 F.3d 819, 822, 824–27 (11th
Cir. 1996)). The district court denied Davis’s motion,
consistent with the Eleventh Circuit’s law at the time. While
                  UNITED STATES V. LUSTIG                      11

Davis’s appeal was pending, however, the Supreme Court
held in Arizona v. Gant, 556 U.S. 332 (2009), that vehicle
searches pursuant to arrest are generally forbidden when the
arrestee is out of reaching distance of the vehicle. Davis,
564 U.S. at 234. The Supreme Court in Davis held that,
although Gant made the search of Davis’s car
unconstitutional, the good-faith exception applied because the
search had been “in strict compliance with” “binding
appellate precedent.” Id. at 240–41.

    Here, the Government argues that, like the officers in
Davis, Chiappino reasonably relied on then-binding appellate
precedent authorizing his search of Lustig’s Pocket Phones.
The Government specifically points to United States v.
Robinson, 414 U.S. 218 (1973), in which the Supreme Court
held, seemingly as a categorical matter, that “in the case of a
lawful custodial arrest a full search of the person is not only
an exception to the warrant requirement of the Fourth
Amendment, but is also a ‘reasonable’ search under that
Amendment.” Id. at 235. The Supreme Court emphasized
that “[t]he authority to search the person incident to a lawful
custodial arrest . . . does not depend on . . . the probability in
a particular arrest situation that weapons or evidence would
in fact be found upon the person of the suspect,” because
once there is probable cause to arrest, “a search incident to
the arrest requires no additional justification.” Id. Applying
this broad principle, the Supreme Court held that an officer
had not violated the Fourth Amendment by searching a
crumpled package of cigarettes in the arrestee’s pocket
without a warrant, or by seizing the heroin capsules hidden
therein. Id. at 236.

    We agree with the Government that, before Riley, it was
objectively reasonable to have interpreted Robinson to
12               UNITED STATES V. LUSTIG

announce a bright-line rule authorizing any search incident to
arrest of any item found in an arrestee’s pocket.

                              1

     As a threshold matter, we recognize the obvious fact that
Robinson did not involve searches of cell phones, and indeed
could not have, given the state of technology at the time.
Lustig argues that Robinson’s lack of factual equivalence to
his case is alone sufficient to preclude application of the
good-faith exception under Davis. But, as the Third Circuit
has accurately observed, “[n]o two cases will be factually
identical.” United States v. Katzin, 769 F.3d 163, 176 (3d
Cir. 2014) (en banc), cert. denied, 135 S. Ct. 1448 (2015).
The Third Circuit has explained that the Davis inquiry “is not
answered simply by mechanically comparing the facts of
cases and tallying their similarities and differences. Rather,
[it] involves a holistic examination of whether a reasonable
officer would believe in good faith that binding appellate
precedent authorized certain conduct.” Id. The relevant
determination is thus whether “the rationale underpinning the
[binding appellate precedent] . . . clearly authorized the
[officers’] conduct.” Id. at 173–74 (emphasis added); see
also United States v. Burston, 806 F.3d 1123, 1129 (8th Cir.
2015) (considering whether the purported binding precedent
“provide[s] a rationale to justify [the officer’s] search”);
United States v. Stephens, 764 F.3d 327, 337–38 (4th Cir.
2014) (“[I]t is the legal principle of [the precedent], rather
than the precise factual circumstances, that matters.”), cert.
denied, 136 S. Ct. 43 (2015); United States v. Aguiar,
737 F.3d 251, 260–62 (2d Cir. 2013) (rejecting the contention
that binding appellate precedent must be “specific to the facts
at hand”).
                    UNITED STATES V. LUSTIG                            13

     Our own case law is consistent with this approach to
applying the good-faith exception. In United States v.
Thomas, 726 F.3d 1086, 1094–95 (9th Cir. 2013), we held
that the good-faith exception applied when officers relied on
Supreme Court precedent that was silent on the key fact
motivating the suppression motion. There, the defendant
challenged as unconstitutional a drug-detection dog’s
touching of his vehicle during a dog-sniff inspection of the
vehicle—an inspection that resulted in the discovery and
seizure of marijuana. Id. at 1092. The defendant relied on
two Supreme Court cases decided after the seizure in question
for the proposition that the dog’s physically touching his
vehicle was an unconstitutional trespass prohibited by the
Fourth Amendment.4 Id. at 1092–93. We held that, whether
or not the dog’s physical contact with the car violated the
Fourth Amendment under these later cases, Supreme Court
precedent at the time of the incident categorically authorizing
dog-sniff inspections at vehicle stops made the evidence
admissible under the good-faith exception to the exclusionary
rule. Id. at 1094–95 (citing Illinois v. Caballes, 543 U.S. 405,
410 (2005) (“A dog sniff conducted during a . . . lawful
traffic stop that reveals no information other than the location
of a substance that no individual has any right to possess does
not violate the Fourth Amendment”) (alteration in original),
and City of Indianapolis v. Edmond, 531 U.S. 32, 40 (2000)
(“[A]n exterior sniff of an automobile” is permissible because
it “does not require entry into the car.”)). Although Caballes
and Edmond did not address physical contact with a vehicle,


 4
   Specifically, the defendant relied on United States v. Jones, 132 S. Ct.
945 (2012) (holding that attaching a GPS device to a car constituted a
Fourth Amendment search), and Florida v. Jardines, 133 S. Ct. 1409
(2013) (holding that a dog-sniff conducted in the curtilage of the
defendant’s home was a Fourth Amendment search).
14               UNITED STATES V. LUSTIG

we nevertheless held that the good-faith exception applied
because neither case “so much as hinted that officers were to
avoid contact” between the dog and the vehicle’s exterior.
Thomas, 726 F.3d at 1095. Because the binding case law at
the time of the inspection “specifically authorize[d] a
particular police practice”—exterior dog-sniffs at vehicle
stops—“the absence of a previously expressed limit” on the
categorical rule, rather than a prior endorsement of a
particular subset of factual circumstances, was dispositive of
the good-faith analysis. Id. (quoting Davis, 564 U.S. at 241).

    Following this approach, we reject Lustig’s contention
that the good-faith exception cannot apply here because, at
the time of his arrest, there had not been any decision by this
Circuit or the Supreme Court directly authorizing warrantless
cell phone searches incident to arrest. If precedent had to
constitute a factual match with the circumstances of the
search in question for the good-faith exception to apply, it
would make the good-faith exception a nullity because the
exception would only apply when the search was necessarily
constitutional under existing precedent.

    Considering, then, the legal principles established by
Robinson and not merely its specific facts, we conclude that
Robinson was binding appellate authority that made it
reasonable to search Lustig’s Pocket Phones. Even the
Supreme Court in Riley, which “decline[d] to extend
Robinson” from physical objects to cell phone data,
acknowledged that Robinson had established a “categorical
                     UNITED STATES V. LUSTIG                            15

rule,” and that “a mechanical application of Robinson might
well support” cell phone searches. 134 S. Ct. at 2484–85.5

    Lustig argues, however, that the law governing
warrantless searches of cell phones was unsettled at the time
of the search, thus precluding objectively reasonable reliance
on Robinson. In support, Lustig cites a handful of federal
district court decisions and an Ohio Supreme Court decision
pre-dating the searches here, which had held that cell phone
searches incident to arrest were unconstitutional. See, e.g.,
United States v. Park, No. CR 05-375SI, 2007 WL 1521573,
at *6–9 (N.D. Cal. May 23, 2007); State v. Smith, 920 N.E.2d
949, 954 (Ohio 2009).

    The Davis inquiry, however, is focused on binding
appellate authority, which Lustig’s cases are not. See United
States v. Pineda-Moreno, 688 F.3d 1087, 1090–91 (9th Cir.
2012) (looking to Supreme Court and Ninth Circuit precedent


  5
    The Fifth Circuit—before Riley and before the Pocket Phone searches
at issue here—similarly understood Robinson to authorize searches of cell
phones incident to arrest. See United States v. Finley, 477 F.3d 250,
259–60 (5th Cir. 2007) (holding that, under Robinson, a valid custodial
arrest permits a warrantless search of an individual’s cell phone, including
its call records and text messages). In United States v. Flores-Lopez,
670 F.3d 803, 810 (7th Cir. 2012), also decided before the Pocket Phone
searches here, the Seventh Circuit likewise held that looking in a cell
phone for the cell phone’s number did not exceed what Robinson allows.
Lustig is correct that the Seventh Circuit went on to discuss the unique
features of cell phones, but it explicitly left “for another day” the
constitutionality of a “more extensive search of a cell phone without a
warrant.” Id. The First Circuit eventually held that a search incident to
arrest does not authorize the warrantless search of data on a cell phone
seized from an arrestee’s person, but it did so after the searches at issue
here. See United States v. Wurie, 728 F.3d 1, 13 (1st Cir. 2013), aff’d sub
nom. Riley v. California, 134 S. Ct. 2473 (2014).
16                  UNITED STATES V. LUSTIG

in applying Davis); see also United States v. Taylor, 776 F.3d
513, 517 n.1 (7th Cir. 2015) (per curiam) (noting that courts
applying Davis look to “circuit-level binding appellate
precedent,” but that “[c]ircuits without local precedent . . .
rel[y] on . . . Supreme Court” precedent); United States v.
Barraza-Maldonado, 732 F.3d 865, 867–68 (8th Cir. 2013)
(for the Davis good-faith exception to apply, “officers
performing a particular investigatory action . . . must strictly
comply with binding appellate precedent governing the
jurisdiction in which they are acting”); United States v.
Aguiar, 737 F.3d 251, 261 (2d Cir. 2013) (“binding
precedent” under Davis “refers to the precedent of this Circuit
and the Supreme Court”). Even if state appellate court
decisions could serve as “binding appellate precedent”—a
question we do not decide, see infra n.10—an Ohio state
court appellate decision had no “binding” effect on the
officers’ searches of Lustig’s phones in California. Lustig’s
contrary argument would suggest that police could not rely on
Supreme Court precedent that seems to authorize the search
in question if any district court or state court anywhere in the
country disagreed about the breadth of that precedent. We
decline to impose on law enforcement an obligation to
constantly search for non-binding authority across all
jurisdictions and to curtail their otherwise authorized
activities as soon as any court casts existing precedent into
doubt.6

  6
    A sufficient body of district court or state appellate court decisions
could perhaps create enough uncertainty about the scope of prior appellate
precedent to make it unreasonable to rely on that precedent. See Davis,
564 U.S. at 250–51 (Sotomayor, J., concurring in the judgment) (arguing
that when the “law in the area” is “unsettled,” law enforcement officials
should “err on the side of constitutional behavior”) (quoting United States
v. Johnson, 457 U.S. 537, 561 (1982)). We need not determine here
whether that is so or precisely what would be required to create enough
                     UNITED STATES V. LUSTIG                            17

    Lustig contends that application of the good-faith
exception here is precluded by our decision in United States
v. Camou, 773 F.3d 932 (9th Cir. 2014), which he argues has
already held that the good-faith exception does not apply to
pre-Riley warrantless cell phone searches.               Lustig
misconstrues Camou, which dealt only with the timing of
searches following an arrest. In Camou, United States Border
Patrol agents had stopped the defendant’s truck at an
inspection checkpoint and discovered an undocumented
immigrant hiding in the truck. Id. at 935. The defendant was
placed under arrest and agents seized his truck as well as a
cell phone found in the cab of the truck. Id. One hour and
twenty minutes after the defendant’s arrest, an agent searched
the cell phone and found photographic images of child
pornography. Id. at 936. The defendant was indicted on
child pornography charges and moved to suppress the images
found on his cell phone. Id. The district court denied the
motion and we reversed. Id. at 936–37. We held, inter alia,
that the search of the phone was not incident to arrest because
it was conducted at a time too remote from the arrest, and that
the good-faith exception did not apply because the
“governing law at the time of the search made clear that a
search incident to arrest had to be contemporaneous with the
arrest.” Id. at 944–45 (citing United States v. Hudson,
100 F.3d 1409, 1419 (9th Cir. 1996)).

    Although Camou, in its broadest outlines, is a post-Riley
case holding that the good-faith exception did not apply to a
pre-Riley cell phone search, it did not address the central
issue here—whether, when a cell phone is found during an


uncertainty because it is clear that, in light of Robinson’s seemingly broad
and categorical holding, the handful of decisions that Lustig cites were not
enough to make reliance on Robinson unreasonable.
18                  UNITED STATES V. LUSTIG

otherwise unquestionably valid search incident to arrest, it
may be searched during the arrest without a warrant.7
Because Camou said nothing about the question we face
here—and indeed never mentioned Robinson at all, let alone
its relationship to Riley—it does not foreclose application of
the good-faith exception to the searches of Lustig’s Pocket
Phones.

    Lustig’s reliance on our recent decision in United States
v. Lara, 815 F.3d 605 (9th Cir. 2016)—another post-Riley
case that declined to apply the good-faith exception to a pre-
Riley search of a cell phone—is similarly unavailing. Lara
concerned a warrantless search of a probationer’s cell phone
pursuant to a probation agreement that included a “Fourth
Amendment waiver.” Id. at 607. The Fourth Amendment
waiver provided that the probationer would submit his
“person and property, including any residence, premises,
container or vehicle . . . to search and seizure at any time” by
any officer, “with or without a warrant, probable cause, or
reasonable suspicion.” Id. The probationer was ultimately
charged with being a felon in possession of a firearm and
ammunition based on evidence discovered from a search of
his cell phone. Id. at 608. The probationer moved to
suppress that evidence. Id. On appeal, we held that the
waiver language did not clearly authorize the search in that
case, and that the search was not otherwise a reasonable
probation search. Id. at 610, 612.




  7
    Lustig also challenges the resumption of that initial search four days
later, which we address below.
                    UNITED STATES V. LUSTIG                           19

    In addition, although we rejected the government’s
reliance on the Davis good-faith exception,8 we specifically
distinguished cases involving searches of cell phones incident
to arrest: “It hardly needs saying that a search incident to
arrest is not the same thing as a warrantless, suspicionless,
probation search. Nor is a case dealing with an incidental
search on all fours with a probation search.” Id. at 614.
Given this language in Lara making clear that the questions
it addressed were distinct from the questions posed by
searches incident to arrest, Lara does not help Lustig resist
application of the good-faith exception here.

    Finally, Lustig suggests that Riley tacitly rejected
applying the good-faith exception to cell phone searches. He
points to the fact that the Supreme Court in Riley
unanimously rejected the argument that Robinson extended
to cell phone searches as evidence that it was never
reasonable to think that Robinson authorized such searches.
But the Supreme Court suggested exactly the opposite when
it observed, as noted above, that “mechanical application of
Robinson might well support the warrantless searches at issue
here.” Riley, 134 S. Ct. at 2484.9

  8
    Because in Lara the government had not sought application of the
good-faith exception in the district court, we held that the argument had
not been preserved on appeal. Id. at 613. We nevertheless proceeded to
explain that we would have rejected the argument on the merits even if not
waived. Id.
   9
     Lustig also argues that because Riley affirmed the First Circuit’s
decision in Wurie, which rejected the government’s good-faith exception
arguments, Riley must have done so as well. But Wurie concluded that the
government had waived the good-faith exception, not that the exception
was inapplicable on the merits. See Wurie, 728 F.3d at 13–14 (holding
that because the government “did not invoke the exception before the
district court,” it “entirely failed to carry [its] burden”).
20                  UNITED STATES V. LUSTIG

      Because Robinson, by its terms, “specifically
authorize[d]” the search incident to arrest of an object found
on the arrestee’s person, the good-faith exception makes
admissible the evidence obtained during the searches of the
Pocket Phones incident to Lustig’s arrest.10 Davis, 564 U.S.
at 241 (emphasis omitted). As the First Circuit observed in
discussing another line of precedent, even though this bright-
line rule “turned out not to be as categorical as [it] seemed,
. . . that is not a reason to penalize the police for applying [it]
faithfully before [that] clarification[] occurred.” United
States v. Sparks, 711 F.3d 58, 67 (1st Cir. 2013).

                                    2

    Lustig contends that even if the good-faith exception
saves the searches of the Pocket Phones conducted at the
hotel, the delay between those initial searches and the more
comprehensive stationhouse searches undertaken four days
later rendered the stationhouse searches unconstitutional. We
disagree.



 10
    The Government argues that the California Supreme Court’s decision
in People v. Diaz, 244 P.3d 501 (Cal. 2011), supports the conclusion that
Chiappino could reasonably believe that Robinson authorized the Pocket
Phone searches. Diaz held that, under Robinson, searches of cell phones
discovered directly from an arrestee’s person comported with the Fourth
Amendment. Id. at 505–06. Lustig responds that Diaz is irrelevant
because it is not binding federal appellate authority, and the searches of
his phones were conducted by officers cross-designated as federal agents.
Because we hold that Robinson provides the applicable binding appellate
authority creating a reasonable basis for the Pocket Phone searches here,
and because we may affirm on any ground supported by the record, United
States v. Albers, 136 F.3d 670, 672 (9th Cir. 1998), we need not decide
whether state court decisions such as Diaz have any relevance to the good-
faith analysis here.
                 UNITED STATES V. LUSTIG                    21

    In United States v. Burnette, 698 F.2d 1038 (9th Cir.
1983), we held that once an item “has been lawfully seized
and searched, subsequent searches of that item, so long as it
remains in the legitimate uninterrupted possession of the
police, may be conducted without a warrant.” Id. at 1049. In
specifically holding that a brief search of a purse incident to
arrest and a more detailed warrantless search of the same
purse later at the stationhouse were both constitutional, we
emphasized the “necessarily reduced expectation of privacy
one holds in his person after being placed under arrest” and
the “necessarily reduced” expectation of privacy in an item
already validly searched incident to arrest. Id. “Requiring
police to procure a warrant for subsequent searches of an item
already lawfully searched would in no way provide additional
protection for an individual’s legitimate privacy interests.”
Id. This reasoning applies to the searches here, whether
delayed by four hours or four days. Because the Pocket
Phones were lawfully seized from Lustig’s person and
immediately searched incident to arrest, Burnette fully
authorizes the later searches. At the very least, it was
reasonable for Chiappino to believe that four days was a
permissible delay.

    Lustig argues to the contrary, contending that the four-day
delay is “far more egregious” than the one hour and twenty
minute delay at issue in Camou. See Camou, 773 F.3d at
944–45. Camou, however, did not consider how a
preliminary search at the time of arrest might affect a later
search of the same item. In Camou, there was no search of
the cell phone incident to arrest, so the delayed warrantless
search was the initial search. Camou thus has no bearing
here.
22                 UNITED STATES V. LUSTIG

    In sum, Robinson made it objectively reasonable to
believe that the searches of the Pocket Phones were
constitutional. We further conclude that Burnette authorized
the subsequent stationhouse searches of the Pocket Phones,
or at least provided a basis for a good-faith belief that those
searches were lawful. We therefore affirm the denial of
Lustig’s suppression motion as to the Pocket Phones.

                                  B

    Lustig also challenges the denial of the motion to
suppress evidence obtained through the Car Phone searches.
In its Answering Brief, the Government concedes, citing
United States v. Sullivan, 753 F.3d 845, 855–56 (9th Cir.
2014),11 that it did not present sufficient evidence to show
that the 16-month delay between the seizure of the Car
Phones and the officers’ obtaining a warrant to search them
was reasonable under the Fourth Amendment, and that the
district court therefore erred in denying Lustig’s motion. The
Government argues, however, that the error was harmless. It
contends that because Lustig pled guilty only to charges
involving MF2, whom the Government asserts was identified
exclusively through information obtained from the Pocket
Phones, any evidence derived from the Car Phones was
“immaterial to Lustig’s conviction.” We are not persuaded
that this is the relevant harmlessness inquiry. Rather, as our
sister circuits have held, the relevant question in the
conditional plea context is whether the erroneous suppression
ruling could have affected Lustig’s decision to plead guilty.


  11
     This version of the Sullivan opinion cited by the Government was
subsequently withdrawn and superseded by a revised opinion. See United
States v. Sullivan, 797 F.3d 623 (9th Cir. 2015). The relevant portion
remained substantively unchanged.
                     UNITED STATES V. LUSTIG                         23

Because it could have, we reverse the suppression ruling on
the Car Phones.

                                     1

    As an initial matter, we agree with the Government’s
contention that harmless error review applies here. The
Federal Rules of Criminal Procedure specifically provide,
under the heading “[h]armless [e]rror,” that “[a]ny error,
defect, irregularity, or variance that does not affect substantial
rights must be disregarded.” Fed. R. Crim. P. 52(a). And the
Supreme Court has held that, generally, constitutional errors
in criminal proceedings must be disregarded if the
government can prove that they are harmless “beyond a
reasonable doubt.” Neder v. United States, 527 U.S. 1, 7
(1999) (quoting Chapman v. California, 386 U.S. 18, 24
(1967)).

     Consistent with these general principles, our prior
decisions have applied harmless error review in the Rule
11(a)(2) conditional plea context.12 In United States v.
Richard Davis, 530 F.3d 1069, 1083 (9th Cir. 2008), for
instance, we held that a frisk of the defendant violated his
Fourth Amendment rights and that the district court erred by
failing to suppress the hashish oil discovered as a result of
that frisk. Nevertheless, we held that the error did not

 12
      Federal Rule of Criminal Procedure 11(a)(2) provides:

          With the consent of the court and the government, a
          defendant may enter a conditional plea of guilty or nolo
          contendere, reserving in writing the right to have an
          appellate court review an adverse determination of a
          specified pretrial motion. A defendant who prevails on
          appeal may then withdraw the plea.
24               UNITED STATES V. LUSTIG

mandate reversal because, even without the hashish oil, the
officers had “sufficient [evidence] to establish probable cause
to search [the defendant’s] truck”—a search that ultimately
led to discovery of the marijuana plants that formed the basis
of the defendant’s conviction. Id. at 1076, 1083–84.
Therefore, “[a]ny error by the district court in failing to
suppress the hashish oil was harmless.” Id. at 1084; see also,
e.g., United States v. DiCesare, 765 F.2d 890, 896–99 (9th
Cir.), amended, 777 F.2d 543 (9th Cir. 1985) (reviewing
district court errors for harmless error on appeal from a
conditional plea).

    Lustig’s contention that harmless error review does not
apply in the Rule 11(a)(2) context, and that any error,
however slight or tangential, requires reversal with the
opportunity to withdraw the plea, is incorrect in light of this
precedent. Lustig rests his argument entirely on a statement
in a footnote in our decision in United States v. Mejia,
69 F.3d 309 (9th Cir. 1995), that “[i]f any ruling that forms a
basis for the conditional plea is found to be erroneous, we are
required to permit the defendant to withdraw his plea.” Id. at
316 n.8. In context, it is clear that this sentence was not
stating a general proposition but responded instead to the
particular facts of that case.

    Mejia concerned two motions to suppress, relating to a
confession and consent to search a home, respectively. Both
the confession and the consent to search arose out of an
allegedly unconstitutional interrogation. The error we held
the district court to have made related to a continuance denial
that prevented the defendant from presenting testimony
needed to resolve material fact disputes about the
interrogation. We explained in the same footnote that:
                    UNITED STATES V. LUSTIG                           25

         given the fact that the [two] motions [to
         suppress] were heard together, that they
         related to the same interrogation and involved
         overlapping issues, that the failure to give a
         Miranda warning can be a consideration when
         determining questions of consent, and that the
         court’s error as to both motions was identical,
         we would conclude that, under all the
         circumstances, a showing of prejudice as to
         either would be sufficient to require a finding
         of error and a new hearing as to both.

Id. This factual context shows that the statement Lustig relies
upon cannot be interpreted to broadly foreclose harmless
error review in all instances. Instead, it refers to the
interrelated nature of the two motions and the conditional
plea at issue in that case. Indeed, the need to show that an
error was prejudicial in order for that error to trigger the right
to vacate a plea was clarified in the same footnote by the
phrase “a showing of prejudice as to either [motion] would be
sufficient to require a finding of error and a new hearing as to
both.” Id. (emphasis added).

    This understanding of Rule 11(a)(2) is consistent with the
approaches of other circuits, which likewise have applied
harmless error type principles in the conditional plea context.
See, e.g., United States v. Benard, 680 F.3d 1206, 1212–15
(10th Cir. 2012); see also United States v. Peyton, 745 F.3d
546, 557 (D.C. Cir. 2014); United States v. Leake, 95 F.3d
409, 420 n.21 (6th Cir. 1996).13 We thus agree with the


  13
     Peyton and Leake framed the issue as whether the defendant had
“prevail[ed] on appeal” for purposes of Rule 11(a)(2), rather than whether
the district court error was “harmless.” See Peyton, 745 F. 3d at 557;
26                  UNITED STATES V. LUSTIG

Government that harmless error review applies to the district
court’s failure to suppress the fruit of the Car Phone searches.

                                    2

    Having established that harmless error review applies in
Rule 11(a)(2) appeals, we must now determine the standards
that govern that review. The Government urges us to adopt
a standard that defines an error as harmless when we can
conclude, beyond a reasonable doubt, that the evidence
erroneously admitted was “immaterial to [the defendant’s]
conviction.” Our cases have not directly addressed this issue,
but Rule 11(a)(2) itself and authority from our sister circuits
cause us to believe that the correct standard is instead whether
the government has proved beyond a reasonable doubt that
the erroneously denied suppression motion did not contribute
to the defendant’s decision to plead guilty.

    The critical event for a defendant in a conditional plea
context is the decision to plead guilty after considering what
a trial would entail in light of the failed pretrial motions.
Rule 11(a)(2) allows a defendant, having lost certain pretrial
motions, to plead guilty while reserving the right to appeal
those pretrial rulings. See Fed. R. Crim. P. 11, advisory
committee’s note to 1983 amendment (stating that the
purpose of subsection (a)(2) is to avoid forcing “a defendant
who has lost one or more pretrial motions” to “go through an
entire trial simply to preserve the pretrial issues for later
appellate review”). As the Tenth Circuit has held, unlike in


Leake, 95 F.3d at 419–20 & n.21. However framed, the ultimate question
is the same: when is a defendant entitled to withdraw his plea due to the
district court’s error? If an error is deemed harmless, then the defendant
will not have “prevail[ed] on appeal,” and vice versa.
                      UNITED STATES V. LUSTIG                              27

cases decided by a jury, in which constitutional error will be
harmless if the court concludes “beyond a reasonable doubt
that the error complained of did not contribute to the verdict
obtained,” United States v. Benard, 680 F.3d 1206, 1213
(10th Cir. 2012) (quoting Chapman, 386 U.S. at 24), for
convictions based on conditional guilty pleas, the test must be
“reformulated to determine whether there is a reasonable
possibility that the error contributed to the plea,” id.
(emphasis added) (quoting People v. Grant, 380 N.E.2d 257,
264 (N.Y. 1978)); see also United States v. Molina-Gomez,
781 F.3d 13, 25 (1st Cir. 2015) (considering whether
suppression of the contested evidence “would have affected
[the defendant’s] decision to plead guilty”). It is thus whether
the evidence at issue in an erroneously denied suppression
motion could have affected the defendant’s decision to plead
guilty, not whether the evidence was material to a charge to
which the defendant pled, that determines whether the
suppression error was harmless in a conditional plea context.

    The relevant inquiry in this case is thus whether there is
a “reasonable possibility”14 that the erroneously admitted Car
Phone evidence contributed to Lustig’s decision to plead
guilty. Benard, 680 F.3d at 1213. This “reasonable
possibility” standard is necessarily hard for the government
to meet. This is because, as the Tenth Circuit has explained,


   14
      In the Tenth Circuit’s formulation, which we adopt here, concluding
that there is a “reasonable possibility” that the error contributed to the plea
decision is the opposite of concluding “beyond a reasonable doubt that the
. . . error did not contribute” to the plea decision. Benard, 680 F.3d at
1214 (emphasis added). In other words, an error will be harmless for Rule
11(a)(2) purposes if an appellate court can conclude beyond a reasonable
doubt that the error did not contribute to the defendant’s decision to plead
guilty, but will not be harmless if there is a reasonable possibility that the
error did contribute to the decision to plead guilty.
28                UNITED STATES V. LUSTIG

“in the context of a plea, the record will be unlikely to contain
enough information for an appellate court” to conclude
beyond a reasonable doubt that the evidence did or did not
contribute to the defendant’s plea decision. Id. A
“defendant’s decision to plead guilty may be based on any
factor inside or outside the record,” id. (quoting Grant,
380 N.E.2d at 264), and “only the defendant is in a position
to evaluate the impact of a particular erroneous refusal to
suppress evidence,” id. (citation omitted) (quoting Jones v.
Wisconsin, 562 F.2d 440, 445 (7th Cir. 1977)).
“Accordingly, ‘an appellate court will rarely, if ever, be able
to determine whether an erroneous denial of a motion to
suppress contributed to the defendant’s decision [to plead
guilty], unless at the time of the plea he states or reveals his
reason for pleading guilty.’” Id. (alteration in original)
(quoting Grant, 380 N.E.2d at 265)).

    Applying these principles, the Tenth Circuit in Benard
rejected the government’s argument that the suppression error
there was harmless because the key firearm evidence
supporting the firearm conviction that determined the
defendant’s ultimate sentence was not affected by the error.
Id. Instead, the Tenth Circuit held that it was unable to
“conclude beyond a reasonable doubt that the district court’s
error did not contribute to [the defendant’s] decision to plead
guilty. The record does not indicate why [the defendant]
decided to plead guilty, what other defenses or evidence he
might have produced on his behalf, or how the altered
bargaining positions of the parties might have affected his
decision if his post-arrest statements had been properly
suppressed.” Id. at 1214.

   Further, the Tenth Circuit rejected the government’s
contention in Benard that, on remand, the case should be
                  UNITED STATES V. LUSTIG                     29

limited to the defendant’s firearm conviction because the
suppression error implicated only the defendant’s drug
conviction. Id. The Tenth Circuit explained that a reviewing
court should consider the error’s effect on the “bargaining
positions of the parties” in light of “the aggregate strength of
all the incriminating evidence accumulated by the
government,” including evidence on other counts. Id.
(alteration omitted) (quoting People v. Miller, 658 P.2d 1320,
1325–26 (Cal. 1983) (in bank)). “[F]inding the suppression
error to affect only some counts of a multi-count indictment
would interfere with the defendant’s ‘prerogative to
personally decide whether to stand trial or to waive his rights
by pleading guilty’ to the various counts of the indictment.”
Id. (quoting People v. Hill, 528 P.2d 1, 29 (Cal. 1974),
overruled on other grounds by People v. Devaughn, 558 P.2d
889 (Cal. 1977) (in bank)). Because the Tenth Circuit could
not conclude beyond a reasonable doubt that the defendant
“would still have agreed to waive his right to a jury trial as to
either or both of the counts of conviction absent the district
court’s error,” it remanded “both counts of conviction under
Rule 11(a)(2).” Id. at 1214–15.

    Other circuits are in accord with these principles. The
Sixth Circuit in United States v. Leake, 95 F.3d 409 (6th Cir.
1996), for example, articulated a standard substantially
similar to the Tenth Circuit’s for determining when a
defendant would be entitled to withdraw his plea, requiring
consideration of “the probability that the excluded evidence
would have had a material effect on the defendant’s decision
to plead guilty.” Id. at 420 n.21 (emphasis added). The D.C.
Circuit has adopted a similar test. See United States v.
Peyton, 745 F.3d 546, 557 (D.C. Cir. 2014) (quoting Leake to
conclude that the defendant was entitled to withdraw his
plea); see also United States v. Burns, 684 F.2d 1066, 1076
30                   UNITED STATES V. LUSTIG

(2d Cir. 1982) (addressing conditional pleas prior to Rule
11(a)(2) and holding that failure to suppress evidence was
harmless error because suppression “would not have altered
appellant’s decision to plead guilty”).

    Recently, the First Circuit arguably applied a
harmlessness standard even harder (or impossible) for the
government to satisfy when it remanded a case to allow the
defendant to withdraw his guilty plea despite noting that “it
is highly unlikely that the suppression of [the statements in
question] regarding drug trafficking activity . . . would have
affected [the defendant’s] decision to plead guilty.” United
States v. Molina-Gomez, 781 F.3d 13, 25 (1st Cir. 2015). The
First Circuit explained that determining whether the
defendant would have pled guilty absent the error was “not
our decision to make. . . . ‘[A] court has no right to decide for
a defendant that his decision [to plead guilty] would have
been the same had the evidence the court considers harmless
not been present.’” Id. (second alteration in original)
(quoting United States v. Weber, 668 F.2d 552, 562 (1st Cir.
1981)). The defendant “is entitled to determine for himself
whether he still wishes to plead guilty given the suppression
of the drug-trafficking-related statements.” Id.

   Insofar as Molina-Gomez may be read to mandate remand
on any error without considering harmlessness,15 our

 15
    It is unclear to what extent, if any, the First Circuit intended to adopt
a different standard than that articulated in Benard, given that it relied in
Molina-Gomez on the same authority as Benard to establish an appellate
court’s limited role in determining harmless error under Rule 11(a)(2).
See Molina-Gomez, 781 F.3d at 25 (quoting Weber, 668 F.2d at 562, and
noting that Weber “adopt[ed] the rationale of the Seventh Circuit and
numerous state courts,” namely Jones v. Wisconsin, 562 F.2d 440 (7th Cir.
1977), People v. Grant, 380 N.E.2d 257 (N.Y. 1978), and People v. Hill,
                    UNITED STATES V. LUSTIG                      31

precedents applying harmless error review, described above,
foreclose adopting such a blanket rule. See, e.g., Richard
Davis, 530 F.3d at 1083; see also Miller v. Gammie, 335 F.3d
889, 892–93 (9th Cir. 2003) (en banc) (holding that a three-
judge panel is bound by prior circuit precedent unless “clearly
irreconcilable . . . intervening higher authority” “effectively
overrule[s]” the precedent). We instead adopt the rule
articulated by a plurality of the circuit courts, under which we
must consider whether an erroneous denial of a motion to
suppress contributed to the defendant’s decision to plead
guilty, and under which it is only the “rare[]” case in which
we may definitively make the harmlessness determination
necessary to preclude remand. Benard, 680 F.3d at 1213; see
also United States v. Mikolon, 719 F.3d 1184, 1188–89 (10th
Cir. 2013) (recognizing Benard’s standard for allowing the
defendant to vacate the plea but concluding beyond a
reasonable doubt that any error did not contribute to the
defendant’s decision to plead guilty because “[t]he
government unequivocally represented to [the defendant] and
the court that it would not seek to admit [the defendant’s]
statements at trial” and thereby took the contested statements
“off the table”).

    Contrary to the Government’s arguments, our precedent
is not inconsistent with a Rule 11(a)(2) inquiry that looks to
the decision to plead guilty rather than the relationship of the
wrongfully admitted evidence to the conviction. Although
we noted in United States v. Sines, 761 F.2d 1434, 1442 (9th
Cir. 1985), that the evidence wrongfully admitted was
“immaterial to [the defendant’s] conviction,” that case did not
mention, much less consider, the essential distinction between
evidence of underlying guilt and evidence that could


528 P.2d 1 (Cal. 1974), all of which Benard also relied upon).
32                  UNITED STATES V. LUSTIG

contribute to a plea decision in the Rule 11(a)(2) context.
Moreover, even if it had, it is unlikely that that distinction
would have made a difference to the outcome of that
particular case. Sines was an example of the “rare” case in
which it was clear that the wrongfully admitted evidence
made no difference either to the decision to plead guilty or to
the conviction. The evidence at issue in Sines was the
defendant’s passport, which the prosecution could have used
to corroborate a witness’s testimony that the defendant was
in Thailand at the relevant time. Id. We determined,
however, that the passport was entirely unnecessary for that
purpose because other ample and admissible evidence served
the same function. Id. Furthermore, the prosecution did not
even mention the passport as part of the evidence against the
defendant during the defendant’s nolo contendere plea
colloquy, despite mentioning all of the other evidence that
proved his presence in Thailand. Id. The passport was thus
unambiguously not a factor in the case.16

    In sum, in light of the purpose and effect of Rule 11(a)(2)
and our existing case law, we agree with the approach taken
by at least the plurality of our sister circuits for analyzing
whether an error is harmless under Rule 11(a)(2). If it is
beyond a reasonable doubt that the error did not contribute to
the decision to plead guilty, it will be considered harmless.
Otherwise, the error will require a remand to provide an
opportunity for the defendant to vacate the guilty plea.


     16
     The Government also relies on United States v. Richard Davis,
530 F.3d 1069 (9th Cir. 2008), to argue for a harmlessness standard that
looks solely at the relationship between the evidence in question and the
charges of conviction. But nowhere in Richard Davis did we discuss the
import of the suppression error on either the defendant’s ultimate
conviction or his decision to plead guilty.
                 UNITED STATES V. LUSTIG                    33

                              3

    Applying this framework to the present case, we conclude
that the Government has not met its burden of establishing
harmless error. See United States v. Velarde-Gomez,
269 F.3d 1023, 1035 (9th Cir. 2001) (en banc) (“The burden
of proving a constitutional error harmless beyond a
reasonable doubt rests upon the government.”). The
Government asks and answers the wrong question when it
argues that admission of the Car Phone evidence was
harmless because it was “immaterial to Lustig’s conviction.”
The relevant inquiry is whether the erroneous admission of
the Car Phone evidence was immaterial to Lustig’s decision
to enter a guilty plea. Given the dearth of factual clarity in
the record as to Lustig’s plea considerations, and indeed as to
what evidence, exactly, was derived from the Car Phones, we
cannot conclude beyond a reasonable doubt that the Car
Phone evidence did not contribute to Lustig’s decision to
plead guilty.

    The Government centers its argument on its assertion that
all of the evidence pertaining to MF2—which formed the
basis for the only charges to which Lustig ultimately pled
guilty—was obtained solely from the Kyocera pocket phone
rather than from the Car Phones. But this argument “ignores
the fact that the guilty plea was entered as part of an
agreement involving all of the counts of the [indictment],”
Benard, 680 F.3d at 1214 (alteration in original) (quoting
People v. Miller, 658 P.2d 1320, 1326 (Cal. 1983) (in
bank))—an indictment that initially included not just counts
related to MF2, but also counts related to MF1, about whom
some evidence was found in the Car Phones. The express
terms of Lustig’s conditional plea make explicit that “[i]n
exchange for Defendant’s guilty plea . . . the United States
34               UNITED STATES V. LUSTIG

agrees to dismiss the Indictment without prejudice at the time
of sentencing.” Thus, Lustig’s “decision to plead guilty to
[the MF2-related counts in the superseding information] was
not made in a vacuum independent of the evidence on [the
MF1-related counts].”         Benard, 680 F.3d at 1214.
Considering the “bargaining positions of the parties” in light
of the “aggregate strength of all the incriminating evidence
accumulated by the [government],” id. (alteration in original)
(quoting Miller, 658 P.2d at 1325–26), the Car Phone
evidence could have had some effect on Lustig’s decision to
plead guilty even if that evidence may not have supported the
MF2-related counts of conviction.

    An additional and independent reason to reject the
Government’s harmlessness argument is that it is unclear
what evidence may have constituted the fruit of the Car
Phone searches. The Government relies entirely on a single
declaration by Deputy Chiappino for its assertion that none of
the Car Phone evidence was used to locate the evidence
needed to support the MF2-related charges. But this
declaration was submitted at sentencing, long after the
suppression motions were litigated, and Lustig never had an
opportunity to challenge Chiappino’s statements through
cross-examination. Indeed, at oral argument before this
court, the Government conceded that Chiappino’s statements
were not “tested below.” Lustig, for his part, raises factual
questions as to the order of the searches of the various phones
and had asked the district court to hold a hearing to identify
the fruit of the searches. Because the district court denied
Lustig’s motion to suppress the Car Phones, it never had
occasion to hold such a hearing or to make a determination as
to the exact fruit of the searches.
                    UNITED STATES V. LUSTIG                            35

    For these reasons, we simply cannot know “how the
altered bargaining positions of the parties might have affected
[Lustig’s] decision [to plead guilty] if [the Car Phone
evidence and any fruit thereof] had been properly
suppressed.” Benard, 680 F.3d at 1214. We certainly cannot
conclude, as the Government urges, that the Car Phone
evidence was analogous to the redundant, essentially useless
passport that the prosecution disclaimed as evidence in Sines.
See Sines, 761 F.2d at 1442.17 In light of the Government’s
failure to satisfy its burden of proving beyond a reasonable
doubt that the district court’s suppression error was harmless,
we remand to allow Lustig the opportunity to withdraw his
guilty plea.18

                                   IV.

    The district court’s denial of the motion to suppress
evidence from the Pocket Phones is AFFIRMED. We
REVERSE the district court’s denial of the motion to
suppress evidence from the Car Phones and REMAND for
further proceedings consistent with this opinion.

 17
   Although the district court indicated that Lustig’s motion to reconsider
the Car Phone suppression ruling was “moot” due to the Government’s
self-suppression of the Car Phone evidence, the Government never
actually stated that it would refrain from using the Car Phone evidence to
prosecute its case. Instead, it stated that “to some extent we don’t intend
to use the evidence from the cell phones seized in the car.” This is a far
cry from disavowing the Car Phone evidence altogether.
  18
     On remand, before Lustig is required to make a decision on whether
to vacate his plea, Lustig should be given an opportunity to renew his
motion to exclude any fruit of the Car Phone searches. See United States
v. Allard, 600 F.2d 1301, 1305–06 (9th Cir. 1979) (“Because the question
of taint was not fully explored below, we must remand for resolution of
the remaining factual questions.”).
36               UNITED STATES V. LUSTIG



WATFORD, Circuit Judge, concurring:

    I join the court’s opinion but write separately to highlight
one aspect of the court’s reasoning that I cannot fully
embrace. The court holds that, even though we are reversing
in part the district court’s denial of Lustig’s motion to
suppress, he’s not automatically entitled to withdraw his
guilty plea. Instead, the court concludes that we must engage
in “harmless error review” to determine whether the district
court’s partially erroneous denial of the motion “contributed
to [Lustig’s] decision to plead guilty.” Maj. op. at 26, 31.

    I do not think Federal Rule of Criminal Procedure
11(a)(2)—or basic principles of contract law, which govern
plea agreements—permit any such inquiry. In my view, if
our court does anything other than affirm in full the district
court’s denial of Lustig’s suppression motion, he is entitled
to withdraw his guilty plea without more. The harmless error
analysis the court engages in has no place in this context.

     That conclusion is dictated by the plain language of Rule
11(a)(2), a short, two-sentence provision added in 1983. The
first sentence authorizes a new type of guilty plea—the
“conditional” plea—that had not previously been sanctioned
by rule or statute: “With the consent of the court and the
government, a defendant may enter a conditional plea of
guilty or nolo contendere, reserving in writing the right to
have an appellate court review an adverse determination of a
specified pretrial motion.” Adding this provision was
necessary because a number of courts had held, prior to the
Rule’s amendment in 1983, that conditional pleas were not
permissible. A defendant either had to plead guilty
                 UNITED STATES V. LUSTIG                     37

unconditionally and waive appellate review of adverse pre-
trial rulings, or, if the defendant sought to preserve such
review, he had to plead not guilty and proceed through trial,
an often wasteful exercise with a foregone conclusion. See
Fed. R. Crim. P. 11(a) advisory committee’s note to 1983
amendments. Rule 11(a)(2) avoids that undesirable state of
affairs by allowing a defendant, with the government’s and
the court’s consent, to plead guilty on the condition that a
specified adverse ruling is ultimately affirmed on appeal.
United States v. Carrasco, 786 F.2d 1452, 1454 (9th Cir.
1986), overruled on other grounds by United States v.
Castillo, 496 F.3d 947 (9th Cir. 2007). The second sentence
of the Rule states what happens if the condition does not
hold: “A defendant who prevails on appeal may then
withdraw the plea.”

    In a case in which the defendant reserves the right to
challenge a single adverse ruling and that ruling ultimately
gets reversed in full on appeal, the application of Rule
11(a)(2)’s second sentence is simple. The defendant has
obviously “prevail[ed] on appeal” and as a result must be
afforded an opportunity to withdraw his plea. United States
v. Botello-Rosales, 728 F.3d 865, 868 (9th Cir. 2013) (per
curiam). I think the application of the Rule is just as simple
when, as in this case, the defendant prevails in part on appeal.
As we said in Carrasco, a Rule 11(a)(2) plea is “conditioned
on the appellate court’s affirmance of the adverse pretrial
ruling.” 786 F.2d at 1454. If the appellate court does
anything other than affirm the specified ruling (or rulings) in
full, then the condition is not satisfied. That means, under
basic contract law principles, that the defendant is entitled to
withdraw from his end of the bargain. See United States v.
Bundy, 392 F.3d 641, 649 (4th Cir. 2004). There is no place
for an appellate court to decide that the partial victory the
38               UNITED STATES V. LUSTIG

defendant won on appeal is too insignificant to warrant the
defendant’s backing out of the deal. See United States v.
Molina-Gomez, 781 F.3d 13, 25 (1st Cir. 2015).

    Here, Lustig agreed to plead guilty on the condition that
the ruling denying his motion to suppress would be affirmed
on appeal. It didn’t get affirmed; it got reversed in part with
respect to the car phones. Thus, the one condition Lustig
placed on his agreement to plead guilty wasn’t satisfied, and
only he gets to decide whether the partial victory he won on
appeal is too inconsequential to justify backing out of the
deal.

    The parties, of course, could have struck a different deal.
Nothing in the language of Rule 11(a)(2) precludes a
defendant and the government from agreeing that the
defendant’s guilty plea will stand unless he wins reversal in
full of a particular adverse ruling. Or, in cases in which the
defendant challenges several distinct adverse rulings, that his
guilty plea will stand unless he wins reversal of all of them.
That’s why the drafters of Rule 11(a)(2) inserted the
requirement that a conditional plea may be entered only with
the government’s consent—to ensure that the defendant could
not insist upon reserving the right to appeal some
inconsequential pre-trial ruling, the reversal of which would
not have any appreciable impact on the outcome of the case.
See Fed. R. Crim. P. 11(a) advisory committee’s note to 1983
amendments (“As for consent by the government, it will
ensure that conditional pleas will be allowed only when the
decision of the court of appeals will dispose of the case either
by allowing the plea to stand or by such action as compelling
dismissal of the indictment or suppressing essential
evidence.”). But the key point here is that if the parties do
not qualify the condition that a particular adverse ruling must
                  UNITED STATES V. LUSTIG                     39

be affirmed on appeal in order for the plea to stand, then a
defendant who wins even partial reversal will be entitled
under the terms of the agreement to withdraw his plea. See
United States v. Mejia, 69 F.3d 309, 316–17 n.8 (9th Cir.
1995).

     There is a place for harmless error review in the context
of conditional pleas, but it differs from the kind of harmless
error review the court engages in here. Appellate courts
always have the authority to determine that, even though the
district court’s reasoning was flawed in some respect, the
district court’s bottom-line ruling is nonetheless correct and
should be affirmed. Or, in like fashion, that the district
court’s ruling on a subsidiary issue was erroneous, but that
the court’s bottom-line decision to deny a suppression motion
is still correct, albeit for reasons that differ from those given
by the district court. See, e.g., United States v. Davis,
530 F.3d 1069, 1083–85 (9th Cir. 2008). In those
circumstances we say the district court’s errors are
“harmless” in the sense that they do not affect the ultimate
disposition of the appeal—the district court’s bottom-line
ruling still gets affirmed.

     That kind of harmless error review is perfectly proper in
the context of Rule 11(a)(2) pleas. See United States v.
Rivera-Nevarez, 418 F.3d 1104, 1111–12 (10th Cir. 2005).
It allows the court to determine, as the court did in Davis, that
the defendant ultimately won no victory on appeal—not even
a partial one—and thus that he cannot be said, in the language
of Rule 11(a)(2), to have “prevail[ed] on appeal.” In such
cases, the court uses harmless error review to affirm in full
the ruling that the defendant reserved the right to challenge on
appeal. See, e.g., Davis, 530 F.3d at 1083–85. The
defendants in cases like Davis are not entitled to withdraw
40                UNITED STATES V. LUSTIG

their conditional guilty pleas because the condition attached
to their pleas is satisfied. This case has to come out
differently because the condition attached to Lustig’s plea
was not satisfied. We did not affirm in full the district court’s
ruling on Lustig’s motion to suppress.

    In short, I agree with the court that Lustig’s convictions
must be vacated, and on remand he must be afforded an
opportunity to withdraw his guilty plea. In my view, though,
that result follows from an application of the plain language
of Rule 11(a)(2) and basic contract law principles, not from
an application of harmless error review.
