                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                 No. 05-10205
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-04-00241-JAT
LIONEL MENDEZ,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
                for the District of Arizona
       James A. Teilborg, District Judge, Presiding

                  Argued and Submitted
       February 16, 2006—San Francisco, California

                  Filed October 30, 2006

      Before: Stephen Reinhardt, Richard A. Paez, and
            Richard C. Tallman, Circuit Judges.

               Opinion by Judge Reinhardt;
                Dissent by Judge Tallman




                           18019
                   UNITED STATES v. MENDEZ                 18023


                          COUNSEL

Jon M. Sands & Michael D. Gordon, Federal Public
Defender, Phoenix, Arizona, for the defendant-appellant.

Paul K. Charlton, John Joseph Tuchi & Bill C. Solomon,
United States Attorney, Phoenix, Arizona, for the plaintiff-
appellee.


                          OPINION

REINHARDT, Circuit Judge:

   On a December evening in 2003, appellant Lionel Mendez
was pulled over by two police officers for failure to display
a visible license plate or registration tag. He was asked to exit
the vehicle, patted down for weapons and, although there
were three small children in the car, told to sit on the curb
behind the vehicle while a records check was conducted. In
response to questioning about matters unrelated to the purpose
of the traffic stop, Mendez ultimately told the officers that
there was a gun in the car, at which point they arrested him,
searched the car and found the gun. After the district court
denied his motion to suppress the evidence, Mendez entered
a conditional plea of guilty to being a felon in possession of
a firearm, in violation of 18 U.S.C. §§ 922(g)(1) and
924(a)(2). The only issue on appeal is whether the district
court erred when it denied his motion to suppress. We con-
clude that it did, vacate Mendez’s conviction and remand.
18024                  UNITED STATES v. MENDEZ
      I.   FACTUAL AND PROCEDURAL HISTORY1

   At approximately 9:18 p.m. on December 21, 2003, two
Phoenix gang enforcement officers pulled over a car driven
by Mendez because they mistakenly thought that it did not
have a license plate or temporary registration tag.2 Both offi-
cers testified that the sole purpose of the stop was “no regis-
tration.” The officers, Detectives Jaensson and Bracke,
approached the car and saw that there were three small chil-
dren inside. Det. Jaensson told Mendez why they had stopped
him and asked for “his identification or license.” Mendez
presented a California identification card. Det. Jaensson then
instructed him to get out of the vehicle and interlock his hands
behind his head. He proceeded to pat him down for weapons,
during which time he noticed a tattoo on his left hand.
Mendez complied without incident. The pat-down produced
  1
     Our recitation of the facts is based primarily on the testimony adduced
at the suppression hearing. Detectives Jaensson and Bracke testified;
Mendez did not.
   2
     The dissent describes the area in which Mendez was stopped as a
“gang area.” However, any such determination “requires careful examina-
tion by the court, because such a description, unless properly limited and
factually based, can easily serve as a proxy for race or ethnicity.” United
States v. Montero-Camargo, 208 F.3d 1122, 1138 (9th Cir. 2000) (en
banc) (discussing the labeling of an area as “high-crime,” but equally
applicable to the “gang area” label). Thus, we have determined that
“[d]istrict courts must carefully examine the testimony of police officers
in cases such as this,” and have emphasized the importance of being “par-
ticularly careful” to ensure that such a characterization “is not used with
respect to entire neighborhoods or communities in which members of
minority groups regularly go about their daily business, but is limited to
specific, circumscribed locations.” Id. The district court made no such
determination before characterizing the area as a gang area. Nor were
there grounds to do so. The officers did not describe the neighborhood as
such during the suppression hearing or offer any facts to support such a
conclusion. That defense counsel accepted the district court’s characteriza-
tion in order to refute the court’s suggestion does not eliminate the neces-
sity of ensuring that such a characterization is properly made. Equally
important, the district court did not rely on the characterization to support
its finding of reasonable suspicion.
                       UNITED STATES v. MENDEZ                       18025
no weapons. Det. Jaensson then instructed Mendez to sit on
the curb behind his car. The three small children remained in
the vehicle unattended.

   Det. Jaensson stayed with Mendez at the curb while Det.
Bracke took his identification card to the patrol car to conduct
a records check. Det. Jaensson again noticed the tattoo on
Mendez’s left hand, recognizing it as a gang-affiliated insignia.3
Prompted by the gang tattoo, he questioned Mendez, asking,
“Where are you from?” According to Det. Jaensson, Mendez
responded that he was “from the Latin Kings,” a gang located
in Chicago. Det. Jaensson testified that he then continued the
questioning, next asking Mendez about his other tattoos. In
response to Det. Jaensson’s interrogation, Mendez said at
some point that he had left the Latin Kings “in good stand-
ing,” and had moved to Arizona “to get away from all that,
to turn his life around.”4

  While a portion, at least, of Det. Jaensson’s interrogation of
Mendez was taking place, Det. Bracke was at the patrol car
conducting a records check, using the car’s Mobile Data Ter-
minal (“MDT”).5 At this time, he noticed in the rear window
   3
     The tattoo, which displayed a lion wearing a five-point crown and the
letters “LK,” aroused Det. Jaensson’s suspicion that Mendez was affiliated
with a Chicago-based street gang known as the “Latin Kings.”
   4
     The record does not reveal at what point during the questioning
Mendez disclosed this information, or the substance of the precise ques-
tions asked by Det. Jaensson. Although the district court made no findings
on this point, it is evident from the record that Mendez did not disclose
the information regarding the reason for his move to Arizona in response
to Det. Jaensson’s first question. Det. Bracke heard this response after he
completed a records check, almost eight minutes after the initial stop.
Regardless of how this information came out in the course of Det. Jaen-
sson’s interrogation, there is no relevant factual dispute about what hap-
pened with respect to Det. Bracke’s later questions and Mendez’s answers
to them.
   5
     The MDT is the computer in the patrol car that the officers use to con-
duct records checks.
18026                  UNITED STATES v. MENDEZ
of Mendez’s vehicle a temporary registration plate that had
expired eight days earlier on December 13, 2003.

   After completing the records check, which revealed that
Mendez had a valid driver’s license and no outstanding war-
rants, Det. Bracke returned to the curb with the intention of
informing him that the temporary registration plate in his rear
window had expired. At that time, he overheard Mendez tell-
ing Det. Jaensson, in response to the detective’s questioning,
that he had come to Arizona “trying to get away from the
gang life.”6 Det. Bracke also overhead him answer that he had
spent time in prison in Illinois. Det. Bracke then questioned
Mendez as to why he had been imprisoned.7 Mendez replied
that he had been convicted of a weapons violation. Det.
Bracke then asked him if he had any weapons in the car.
According to Det. Jaensson and Det. Bracke’s testimony,
Mendez became agitated, told them that he was a good father
and was trying to make a good life for himself in Arizona, and
then said that there was a firearm in the driver’s door handle.
At this point, the officers arrested him. Det. Bracke then
  6
     Det. Bracke also testified that he heard Mendez state that he had been,
or was, a member of the Latin Kings. Whether the detectives believed that
Mendez was a former or current gang member — and there is no testi-
mony on this point — is irrelevant to our disposition of this case: our anal-
ysis is the same on either set of facts.
   7
     Det. Bracke initially testified that Mendez had “volunteered” that his
prison term was for a weapons violation, but shortly thereafter he cor-
rected himself, stating, “I believe I may have, in fact, asked him” why he
had spent time in prison. Moments earlier in his testimony, Det. Bracke
testified, “I did, in fact, ask [Mendez] something after he informed us that
he had spent time in prison in Illinois.” Det. Jaensson similarly testified
that “Det. Bracke may have specifically asked a question” regarding
Mendez’s prison term. By contrast, the written police report, which was
filed seven months earlier on January 2, 2004, makes no mention of the
fact that Det. Bracke questioned Mendez about his prison term; instead,
it merely states that Mendez “told detectives that he had just spent eight
years in the Illinois State Department of Corrections for a weapons viola-
tion.” At oral argument before this court, the government conceded that
Det. Bracke had in fact asked Mendez why he had been imprisoned.
                       UNITED STATES v. MENDEZ                       18027
searched the vehicle and found a loaded, small caliber, semi-
automatic pistol in the driver’s side armrest.

   Mendez was indicted on charges of violating 18 U.S.C.
§§ 922(g)(1) and 924(a)(2) (felon in possession of a firearm).8
He moved to suppress the handgun, arguing that the officers
improperly interrogated him about matters unrelated to the
traffic stop and failed to diligently investigate the purpose of
the stop. The district court denied the motion, finding that the
detectives “identified specific, objective factors sufficient to
permit them to expand the scope of questioning” and did not
unreasonably prolong the stop. Mendez subsequently entered
a conditional guilty plea, preserving his right to appeal the
court’s ruling on the suppression motion. The district court
sentenced him to fifty-seven months in prison. He appeals.

                         II.   DISCUSSION

   Mendez does not contest the legality of the initial traffic
stop. Instead, he argues that the officers’ unrelated question-
ing and extended detention violated his Fourth Amendment
rights because (1) the officers did not observe additional par-
ticularized, objective factors sufficient to create reasonable
suspicion to justify interrogating him about matters beyond
the purpose of the stop, and (2) the officers unreasonably pro-
longed the stop.9 The government responds that there were
  8
     Section 922(g)(1) prohibits any person “who has been convicted in any
court of, a crime punishable by imprisonment for a term exceeding one
year . . . [from] possess[ing] . . . any firearm or ammunition.” 18 U.S.C.
§ 922(g)(1). Section 924(a)(2) provides, in relevant part, that anyone who
knowingly violates section 922(g) “shall be fined as provided in this title,
imprisoned not more than 10 years, or both.” Id. § 924(a)(2).
   9
     Because, as we explain below, we conclude that the interrogation of
Mendez was not justified by sufficient “particularized, objective factors,”
we do not address his argument that the officers unlawfully prolonged the
stop under United States v. Sharpe, 470 U.S. 675, 686 (1985). We also
need not consider Mendez’s claim that the officers’ questioning violated
Arizona law. We do note, however, that Mendez forfeited his state law
claim by failing to raise it before the district court in his motion to sup-
press.
18028               UNITED STATES v. MENDEZ
specific, objective factors that justified suspicion of criminal
activity and the expansion of the scope of the questioning. It
does not argue, however, that the questioning was justified by
concerns for officer safety.

A.   Propriety of the Investigatory Questioning

   [1] The limits of the Fourth Amendment “apply to investi-
gative stops of vehicles such as occurred here.” United States
v. Sharpe, 470 U.S. 675, 682 (1985). The scope of an investi-
gative detention “must be carefully tailored to its underlying
justification.” Florida v. Royer, 460 U.S. 491, 500 (1983).
During a traffic stop, a police officer may only “ask questions
that are reasonably related in scope to the justification for his
initiation of contact.” United States v. Murillo, 255 F.3d 1169,
1174 (9th Cir. 2001); see also United States v. Chavez-
Valenzuela, 268 F.3d 719, 724 (9th Cir. 2001) (“An officer
must initially restrict the questions he asks during a stop to
those that are reasonably related to the justification for the
stop.”). An officer may expand the scope of questioning
beyond the initial purpose of the stop only if he “articulate[s]
suspicious factors that are particularized and objective.”
Murillo, 255 F.3d at 1174; see also Chavez-Valenzuela, 268
F.3d at 724 (stating that an officer may expand scope of ques-
tioning “only if he notices particularized, objective factors
arousing his suspicion” (emphasis added)); United States v.
Perez, 37 F.3d 510, 513 (9th Cir. 1994) (same).

   As the Eleventh Circuit held in another traffic stop case,
United States v. Pruitt, 174 F.3d 1215 (11th Cir. 1999), it is
not necessary that questions be designed to pursue a specific
investigatory objective in order for them to violate the Fourth
Amendment. There, the court concluded that “additional
‘fishing expedition’ questions such as ‘What do you do for a
living?’ and ‘How much money did your van cost?’ are sim-
ply irrelevant, and constitute a violation of Terry.” Id. at 1221.
We cited Pruitt with approval in Chavez-Valenzuela. See
Chavez-Valenzuela, 268 F.3d at 724 n.4.
                      UNITED STATES v. MENDEZ                       18029
   [2] In the case before us, the record demonstrates that the
officers asked Mendez a number of questions that were unre-
lated to the purpose of the stop, including questions involving
his gang affiliation and the reason for an out-of-state prison
sentence a number of years earlier. Det. Jaensson began his
questioning by asking Mendez where he was from. Although
we doubt that this question was related to the purpose of the
stop, we will assume its propriety for purposes of this appeal.
Taken literally, the question would probably be permissible,
as it would appear to relate to the locality at which the driv-
er’s license or the vehicle registration would have been
issued. To that extent, it would be related to the traffic stop.10
We assume the lawfulness of the question although in context
it is best understood as an inquiry in colloquial terms about
Mendez’s gang membership — the information it actually
elicited — rather than, as might otherwise be thought, a ques-
tion about the location of his domicile. Indeed, during the sup-
pression hearing, defense counsel asked Det. Jaensson
whether “the questions about where he was from ha[d] any-
thing to do with the traffic stop,” to which Det. Jaensson
responded, “No.”

   Subsequently, in response to Det. Jaensson’s continuing
interrogation, Mendez told the officers that he had been in
prison. Det. Bracke then questioned him about the reason for
his prior incarceration. When Mendez answered that he had
been convicted of a weapons offense, more than eight years
earlier, Det. Bracke asked him whether there were any weap-
ons in the car. It is the eliciting of this information that led
Det. Bracke to ask that final question that is at the center of
this appeal.
  10
    Cf. Berkemer v. McCarty, 468 U.S. 420, 439 (1984) (stating that an
“officer may ask the detainee a moderate number of questions to deter-
mine his identity and to try to obtain information confirming or dispelling
the officer’s suspicions”); Chavez-Valenzuela, 268 F.3d at 724 n.4
(observing that officer’s “inquiries about Chavez-Valenzuela’s starting
point, destination and general travel plans were probably justifiable”).
18030                  UNITED STATES v. MENDEZ
   [3] The government concedes that, in order to question
Mendez about matters unrelated to the initial purpose of the
stop, the detectives’ questioning had to be justified by addi-
tional particularized and objective factors arousing their sus-
picion. See, e.g., Perez, 37 F.3d at 513. Therefore, Det. Jaen-
sson’s further questioning of Mendez about matters related to
his gang affiliation or criminal history would constitute a
Fourth Amendment violation unless the officer had lawfully
“notice[d] particularized, objective factors arousing his suspi-
cion.” Chavez-Venezuela, 268 F.3d at 724. Likewise, Det.
Bracke’s question about the reason for Mendez’s prior con-
viction would have to have been based on “particularized,
objective factors” not themselves discovered through illegal
questioning — factors that are sufficient in themselves to gen-
erate reasonable suspicion of criminal activity. Id. at 726.

  1.    Det. Jaensson’s interrogation regarding Mendez’s
        gang activities

   [4] We begin our analysis of Det. Jaensson’s questioning,
then, by determining what information he could properly con-
sider in forming a reasonable suspicion. We assume, as
explained earlier, that the officers were made aware lawfully
of Mendez’s past or present gang membership. Thus, in order
to assess the constitutionality of Det. Jaensson’s continuing
interrogation, we first consider whether gang membership,
standing alone, justifies a reasonable suspicion of criminal activ-
ity.11 We conclude that it does not, for two reasons.
  11
     We note that, in addition to Mendez’s gang membership, the officers
were aware of two other facts: (1) when asked for “his identification or
license,” Mendez presented a California identification card and not a driv-
er’s license, and (2) the car he was driving had an expired temporary regis-
tration tag. Neither of those facts is, however, relevant to our totality of
the circumstances analysis with respect to the additional questioning. The
production of the identification card constituted an appropriate response to
the officers’ specific request. Although the fact that the registration had
expired may be pertinent to a registration offense, a recently expired regis-
tration does not give rise to reasonable suspicion of involvement in crimi-
                       UNITED STATES v. MENDEZ                        18031
   [5] First, the Supreme Court has made it clear that reason-
able suspicion must be based upon “a particularized and
objective basis for suspecting the particular person stopped of
criminal activity.” United States v. Cortez, 449 U.S. 411, 417-
18 (1981) (emphasis added); see also United States v.
Montero-Camargo, 208 F.3d 1122, 1129 (9th Cir. 2000) (en
banc) (stating that “[t]he requirement of particularized suspi-
cion encompasses . . . suspicion that the particular person
being stopped has committed or is about to commit a crime”);
United States v. Rodriguez-Sanchez, 23 F.3d 1488, 1492 (9th
Cir. 1994) (“Reasonable suspicion requires that the specific
facts and inferences create suspicion that the particular per-
son detained is engaged in criminal activity.” (emphasis
added) (internal quotation marks omitted)), overruled in part
on other grounds by Montero-Camargo, 208 F.3d at 1134
n.22. Reasonable suspicion may not be “based on broad pro-
files which cast suspicion on entire categories of people with-
out any individualized suspicion of the particular person to be
stopped.” Id. at 1492; see also United States v. Rodriguez, 976
F.2d 592, 596 (9th Cir. 1992) (holding that factors relied upon
by border patrol agents to justify vehicle stop “describe too
many individuals to create a reasonable suspicion that this
particular defendant was engaged in criminal activity”
(emphasis added)).

   [6] Mendez’s former or present gang affiliation may arouse
in the mind of the average layperson, as well as of the trained
police officer, a generalized or unspecific suspicion that he is

nal activity, whether considered alone or in combination with gang
affiliation. The only Ninth Circuit case the dissent relies on to the contrary
involves a boat, not a car, where the driver was unable to name the owner
of the boat and had no registration at all. United States v. Thompson, 282
F.3d 673, 678 (9th Cir. 2002). Nor does United States v. Fernandez, 18
F.3d 874 (10th Cir. 1994), hold that an expired registration creates reason-
able suspicion of criminal activity. That case points to the fact that the
driver had proof of a valid registration to support its conclusion that no
reasonable suspicion existed.
18032                  UNITED STATES v. MENDEZ
associated with criminal types and perhaps has engaged in
criminal activity himself. But the fact that an individual is or
was a gang member does not by itself generate the sort of par-
ticularized and legally relevant suspicion that the Fourth
Amendment requires. As one district court has observed,
“One’s status as a gang member, . . . even a gang member
with a known arrest or conviction record, does not, without
more, create the reasonable and articulable suspicion neces-
sary to justify an investigative detention. . . . Terry and its
progeny require some degree of particularized suspicion
beyond gang membership alone.” United States v. Daniel, 804
F. Supp. 1330, 1335 n.10 (D. Nev. 1992).

   Of course, Detectives Jaensson and Bracke were part of the
gang enforcement unit,12 and officers may “draw on their own
experience and specialized training to make inferences from
and deductions about the cumulative information available to
them that might well elude an untrained person.” United
States v. Arvizu, 534 U.S. 266, 273 (2002) (internal quotation
marks omitted). However, “[p]ermissible deductions or ratio-
nal inferences must be grounded in objective facts and be
capable of rational explanation.” United States v. Michael R.,
90 F.3d 340, 346 (9th Cir. 1996). No matter how much “expe-
rience and specialized training” the detectives had in gang-
related matters, the mere fact of Mendez’s admission regard-
ing gang affiliation does not permit “a rational inference” that
he was involved in criminal activity at or about the time of the
stop.

  [7] Second, an officer’s questioning “must be justified by
some objective manifestation that the person stopped is, or is
about to be, engaged in criminal activity.” Cortez, 449 U.S.
  12
    Det. Jaensson testified at the suppression hearing that during his eight
years working for the Phoenix Police Department’s gang enforcement
unit, he had “run across numerous individuals from various gangs and sev-
eral of them from the Latin Kings,” and also “had training in identifying
gang tattoos and gang members.”
                        UNITED STATES v. MENDEZ                        18033
at 417 (emphasis added); see also Brown v. Texas, 443 U.S.
47, 51 (1979) (officers must have “reasonable suspicion,
based on objective facts, that the individual is involved in
criminal activity”) (emphasis added). Although Mendez’s
gang affiliation might arouse suspicion that he was involved
in criminal activity at some point in the past and might lead
a reasonable officer to suspect that he may become involved
in such activity at some point in the future, it does not support
a reasonable inference “that criminal activity may be afoot”
at the time of the stop or that Mendez might commit any par-
ticular offense now or in the future. Terry v. Ohio, 392 U.S.
1, 30 (1968) (emphasis added). As we have observed in
another context,

       Membership in an organization does not reasonably
       lead to any inference as to the conduct of a member
       on a given occasion. In other words, the tendency of
       members of a gang to carry weapons does not lead
       reasonably to any inference as to whether a gang
       member was armed on a given occasion.

Spivey v. Rocha, 194 F.3d 971, 978 (9th Cir. 1999) (internal
quotation marks and citation omitted) (emphasis added).13
Likewise, Mendez’s affiliation with the Latin Kings does not
by itself “reasonably lead to any inference as to [his] conduct”
  13
    Spivey did not involve a Fourth Amendment claim; rather, it con-
cerned whether the trial court properly excluded evidence that two prose-
cution witnesses were gang members. Id. at 977-78. We held that the
exclusion was not error because the fact of gang membership “was not
probative to the question of whether [the witnesses] were armed.” Id. at
978.
   The dissent, in criticizing our reliance on Spivey, appears to argue that
the requirement that there be reasonable inferences to support a depriva-
tion of liberty applies only at trial and has no place in the Terry stop analy-
sis. Terry itself, however, explains that reasonableness is the “central
inquiry” under the Fourth Amendment and requires that an officer act only
on the basis of “specific reasonable inferences which he is entitled to
draw.” Terry, 392 U.S. at 19, 27.
18034              UNITED STATES v. MENDEZ
on the night of the stop. Id. As the district court in Daniel
observed,

    An individual’s membership in a gang may cause a
    police officer to have an “inchoate and unparticular-
    ized suspicion” that the individual’s every waking
    moment is given to criminal behavior. Terry, 392
    U.S. at 27, 88 S.Ct. at 1883. However, it would be
    a perversion of the Fourth Amendment to hold that
    such a suspicion justifies the interruption of that
    individual’s privacy and liberty during any and all of
    those waking moments.

Daniel, 804 F. Supp. at 1335 n.10.

   [8] Indeed, the fact of Mendez’s gang affiliation generates
no more than a generalized “hunch” that he may have com-
mitted crimes in the past or that he may be prone to criminal
behavior in general, but such hunches fall short of the particu-
larized suspicion that the Fourth Amendment requires. See
Chavez-Valenzuela, 268 F.3d at 724 (“[A]n inchoate and
unparticularized suspicion or hunch cannot withstand scrutiny
under the Fourth Amendment.” (internal quotation marks
omitted)). The fact that Mendez told the officers that he had
come to Arizona “trying to get away from the gang life,” only
further demonstrates the extent to which his statement as to
his gang affiliation failed to provide any objective indicium of
ongoing criminal activity on or about the night in question.
We therefore hold that Mendez’s gang membership was not,
standing alone, a particularized, objective factor that war-
ranted expanding the scope of questioning beyond the initial
purpose of the traffic stop. See id. at 726.

   [9] Because Mendez’s gang affiliation was not sufficient to
support a reasonable suspicion of criminal activity, Det. Jaen-
sson’s continuing interrogation, including his questions
regarding Mendez’s tattoos, gang activities, or criminal his-
tory, exceeded the scope of a permissible Terry-traffic-stop
                      UNITED STATES v. MENDEZ                       18035
interrogation. Accordingly, the information obtained as a
result of that questioning may not serve as a lawful basis for
the questioning subsequently engaged in by Det. Bracke.

  2.    Det. Bracke’s questioning of Mendez regarding the
        reason for his prior prison sentence

   The government contends that Det. Bracke was permitted
to expand the scope of questioning beyond that ordinarily per-
mitted in connection with a traffic stop on the basis of a com-
bination of two “particularized, objective” factors: (1)
Mendez’s gang affiliation with the Latin Kings, and (2)
Mendez’s statement that he had served time in prison.14 In
order to assess this claim, we must determine whether the
officers obtained the information regarding these two factors
lawfully and, if so, whether the information obtained gives
rise to reasonable suspicion of criminal activity.

   We have already explained that, questionable or not, we
will assume that the information regarding the Latin Kings
was lawfully obtained, but that gang membership standing
alone is insufficient to give rise to reasonable suspicion of
particularized criminal conduct. We have also explained that
the information that Mendez had served a prison sentence was
obtained unlawfully, during the course of Det. Jaensson’s
unwarranted interrogation. The result is, therefore, that in this
case the combination of the two factors cannot provide a suf-
ficient lawful basis for Det. Bracke’s questioning of Mendez
regarding the nature of his prison sentence. Nor, or course, for
the differing reasons we have explained, can either factor
standing alone.

  We need not rely, however, for our conclusion that Det.
Bracke’s questioning was unlawful solely on our determina-
  14
    The government does not seriously contend that Det. Bracke’s ques-
tioning was “reasonably related to the justification for the stop.” Chavez-
Valenzuela, 268 F.3d at 724.
18036                  UNITED STATES v. MENDEZ
tion that the information regarding Mendez’s prison sentence
was obtained in violation of the Fourth Amendment. Alterna-
tively, we reject the government’s contention that the fact of
Mendez’s former prison sentence and his past or present gang
membership, taken together (even if such information were
obtained lawfully) created a reasonable suspicion that justi-
fied Det. Bracke’s questioning.15 In considering whether the
two factors together could serve to justify Det. Bracke’s
expanded questioning of Mendez, “[w]e must consider these
factors first separately, and then cumulatively.”16 Perez, 37
F.3d at 514.
  15
      The circumstances of the stop provided no additional support for a
reasonable suspicion of criminal wrongdoing at the time of Det. Bracke’s
questioning. When Det. Bracke questioned Mendez about the reason for
his prison term, he had already determined that he had a valid driver’s
license and that his vehicle registration had expired only eight days earlier.
Indeed, Det. Bracke testified that he returned to the curb with the intention
of telling Mendez that his registration had expired. At oral argument, the
government acknowledged that when Det. Bracke questioned Mendez, he
was investigating possible current criminal activity solely on the basis of
the two newly discovered facts that Mendez had acknowledged during the
course of Det. Jaensson’s interrogation — his gang membership and his
earlier prison term.
   16
      Our assessment of each question based on information available at the
time it was asked is not contrary to the Supreme Court’s mandate that we
look at the totality of the circumstances. United States v. Arvizu, 534 U.S.
266, 274-76 (2002). Arvizu involved a single decision by the police to stop
a vehicle. Id. at 277-78. All of the information used by the Court in the
totality inquiry was available at the time of the stop. Id. at 277. This case,
in contrast, involves a number of challenged police actions occurring
sequentially. In such a situation, the totality of the circumstances inquiry
logically applies only to circumstances known at the time of each respec-
tive police action. This is clear because whether an officer acted on the
basis of a reasonable suspicion cannot be determined using information he
discovers subsequently. Moreover, Arvizu’s requirement that we consider
all the information available at the time of the action was in relation to
information that was acquired legally. Id. Arvizu in no way suggests that
unlawfully obtained evidence may be used to establish reasonable suspi-
cion.
                       UNITED STATES v. MENDEZ                       18037
    We have already concluded above that gang membership
alone is not sufficient. See supra Part A.1. Similarly, we have
previously held in other cases that “a prior criminal history
cannot alone establish reasonable suspicion.” Burrell v. McIl-
roy, 423 F.3d 1121, 1124 n.3 (9th Cir. 2005); see also United
States v. Santos, 403 F.3d 1120, 1132 (10th Cir. 2005) (“[A]
prior criminal history is by itself insufficient to create reason-
able suspicion.”); Padilla v. Miller, 143 F. Supp. 2d 453, 470
(M.D. Pa. 1999) (holding that the facts that a motorist “had
a criminal record and was travelling on an interstate highway
. . . are not sufficient to create an objective basis for extending
the scope of the traffic stop to a Terry investigative deten-
tion”).

   [10] While knowledge of prior criminal activity combined
with certain other factors may in some circumstances foster a
reasonable suspicion of current criminal activity, and while
such knowledge may sometimes be taken into account when
an officer considers whether there is a basis for reasonable
suspicion, the fact of a prior prison term alone does not suf-
fice. As another circuit has correctly observed,

       If the law were otherwise, any person with any sort
       of criminal record— or even worse, a person with
       arrests but no convictions — could be subjected to
       a Terry-type investigative stop by a law enforcement
       officer at any time without the need for any other
       justification at all. Any such rule would clearly run
       counter to the requirement of a reasonable suspicion
       ....

United States v. Sandoval, 29 F.3d 537, 543 (10th Cir. 1994).
In short, to rely on Mendez’s prior prison term as the sole
basis for suspecting him of present criminal activity would be
to rely on the very sort of “inchoate and unparticularized sus-
picion or ‘hunch’ ” that the Fourth Amendment forbids.17
  17
    Some individuals with prior convictions may be on probation or
parole and thus subject to special searches or restraints without reasonable
18038                   UNITED STATES v. MENDEZ
Terry, 392 U.S. at 27. Accordingly, in the absence of other
factors, Mendez’s prior prison term is not a sufficiently “par-
ticularized, objective” factor “to justify the extended detention
and inquiry into other criminal activity.” Chavez-Valenzuela,
268 F.3d at 724, 726.

The Factors Considered Cumulatively18

   Having concluded that neither factor, considered individu-
ally, would be sufficient to justify Det. Bracke’s questioning
(even if the information regarding both had been lawfully
obtained), we must now decide whether “taken together they
[would] amount to reasonable suspicion.” United States v.
Sokolow, 490 U.S. 1, 9 (1989). Although “in some circum-
stances the sum may amount to more than its parts[,] [t]he
facts presented in this case . . . whether viewed alone or in
combination, amount to little.” United States v. Jones, 269
F.3d 919, 929 (8th Cir. 2001).

   In United States v. Perez, we held that six factors — the
defendant’s nervous appearance, avoidance of eye contact,
and profuse perspiration, combined with the fact that he was
not the vehicle’s registered owner, was heading to a known
“drug hub,” and had well-manicured hands despite claiming
to be a mechanic — “[t]aken together, . . . amount to reason-
able suspicion” sufficient to justify the officer’s broadening
his line of questioning. 37 F.3d at 514 (quoting Sokolow, 490
U.S. at 9). Similarly in United States v. Baron, 94 F.3d 1312,
1319 (9th Cir. 1996), we held that six factors, “[w]hen consid-
ered cumulatively . . . justified additional questioning” regard-
ing drug activity during a traffic stop. The six factors

suspicion. Such persons’ Fourth Amendment rights may be limited. See
Samson v. California, 126 S. Ct. 2193 (2006). The same is not true for
persons who have served their time and fully paid their debt to society.
   18
      In light of this section, it is unclear why the dissent argues that we fail
to consider the factors cumulatively.
                       UNITED STATES v. MENDEZ                        18039
identified in Baron were: (1) the vehicle did not belong to the
defendant, (2) the defendant could not name the registered
owner, (3) the defendant provided inconsistent stories regard-
ing his travel from California to Phoenix, (4) the “inside of
the vehicle looked too clean and contained no personal
belongings,” (5) there was an “overpowering cherry smell
coming from inside the car,” and (6) the defendant appeared
nervous. Id.; see also Murillo, 255 F.3d at 1174 (holding that
five factors — extreme nervousness, lack of eye contact only
when asked about drug activity, inability to explain travel
plans, elevated heart rate, and evidence of long road trip in a
rental car — were sufficient to justify broadening the scope
of questioning).

   [11] Unlike in Perez, Baron, and Murillo, in which the gov-
ernment cited five or six suspicious factors, all of which
involved the defendant’s conduct during the stop, and all of
which raised suspicions of a particular form of present crimi-
nal activity, drug trafficking, here the government cites only
two factors, neither of which involved suspicious conduct on
Mendez’s part immediately prior to or during the course of
the traffic stop and neither of which suggests current involve-
ment in any particular type of crime.19 When taken together,
the two facts that Mendez is a “former gang member” and a
“convicted felon” indicate nothing more than that Mendez had
a troubled past. They simply do not provide a particularized,
objective basis upon which to infer that Mendez “is, or is
about to be, engaged in criminal activity.” Cortez, 449 U.S.
at 417.
  19
     As explained above, see supra, note 16, in this case the circumstances
justifying the stop are not probative of criminal activity and, thus, the gov-
ernment does not rely on such factors. Moreover, during the stop, Mendez
was forthcoming in his answers to the officers’ questions, lawful and
unlawful, and exhibited no signs of nervousness until after he was asked
the final question, whether he had any weapons in the car. That question,
we hold, was unlawful because it was the product of, as well as a part of,
an unlawful interrogation exceeding the scope of the Terry stop. Thus, the
government properly does not rely on Mendez’s conduct during the course
of the stop to justify the expanded interrogation.
18040                  UNITED STATES v. MENDEZ
   Many individuals with prior convictions are presently, or
were at one time, gang members and vice versa — that is
hardly an unusual combination. To hold that the fact that an
individual was previously convicted of a crime, and was or is
a gang member, is sufficient cause to interrogate him about
general criminal activity whenever he may be subjected to a
Terry stop would infringe upon the fundamental constitutional
rights of many currently law-abiding citizens. Although per-
sons who have committed crimes may be afforded lesser
Fourth Amendment rights while on probation or parole, once
that process is completed and their debt to society has been
fully paid, they are entitled to the same protection against
unreasonable searches and seizures as all other individuals.20

   [12] We therefore conclude that, considering the two fac-
tors together, they do not constitute sufficiently “particular-
ized” and “objective” indicia that give rise to reasonable
suspicion that Mendez was engaged in criminal activity at or
about the time of the stop. See Chavez-Valenzuela, 268 F.3d
at 726. Accordingly, even if the fact that Mendez previously
served a prison sentence were to be considered (notwithstand-
ing our conclusion that the officers obtained that information
as the result of an unlawful interrogation), Det. Bracke’s addi-
tional questioning about matters unrelated to the purpose of
the traffic stop exceeded the scope of a permissible Terry-type
   20
      Our holding is entirely consistent with our decision in Michael R., 90
F.3d 340, in which we upheld an investigatory stop of a vehicle. In that
case, we found that the fact that young men in the car “had haircuts that
were characteristic of gang members has evidentiary significance under
the totality of the circumstances analysis.” Id. at 346. We have held that
gang membership may be a factor when other circumstances that are
themselves inherently suspicious exist. In Michael R., officers based their
investigatory stop on five other factors in addition to the gang-style hair-
cuts. Id. There, we determined that the “clincher” was the fact that, prior
to being pulled over, the young men had engaged in a “street game of cat
and mouse” that caused the plainclothes officer who was driving an
unmarked car to fear that he was in physical danger. Id. at 346-47. By con-
trast, here, Mendez does not question the stop and, concededly, engaged
in no suspicious or threatening behavior.
                      UNITED STATES v. MENDEZ              18041
inquiry and violated the Fourth Amendment. The fruits of that
unlawful questioning must be suppressed.

B.   Officer Safety

   Perhaps recognizing the lack of reasonable suspicion of
ongoing criminal activity, the dissent, unlike the government,
abandons the district court’s basis for justifying the interroga-
tion and search and proposes an entirely different reason for
the intrusion on Mendez’s rights. The district court dismissed
the officer safety argument in a footnote, saying that the offi-
cer safety concerns did not eliminate the reasonable suspicion
requirement, and then deciding that a reasonable suspicion of
criminal activity was present. The dissent, however, relies
exclusively on officer safety concerns to justify Det. Bracke’s
questioning. Its reliance on this new ground is surprising
given the paucity of evidence in the record supporting any
such concern and, more important, given that the government
failed to raise the issue of officer safety on appeal.

   The dissent asks us to reach the issue of officer safety
because “the court may affirm on any ground fairly supported
by the record.” In doing so, it disregards the fact that the gov-
ernment did not present the officer safety issue on appeal. Our
authority to affirm the district court on alternative grounds
does not excuse the parties from their obligation to brief the
issues they wish the court to consider. See, e.g., Scholar v.
Pac. Bell, 963 F.2d 264, 266 (9th Cir. 1992) (explaining that
we ordinarily affirm on alternative grounds only if the issue
is briefed by the parties); United States v. Lewis, 787 F.2d
1318, 1323 n.6 (9th Cir.), as amended on denial of reh’g and
reh’g en banc, 798 F.2d 1250 (9th Cir. 1986) (reversing a
conviction and declining to reach grounds first raised by the
government in its petition for rehearing). If the court reaches
an issue not briefed by the concerned party, the opposing
party is deprived of the opportunity to respond and the court
is deprived of the benefit of briefing. Galvin v. Alaska Dep’t
of Corr., 397 F.3d 1198, 1204 (9th Cir. 2005). Thus, “gener-
18042                UNITED STATES v. MENDEZ
ally courts limit themselves to resolving the issues that the
parties put before them, as opposed to the issues they spot
outside what the parties elect to raise.” Id. at 1204. This is
particularly true where the failure was intentional, as opposed
to inadvertent. Varney v. Sec’y of Health and Human Servs.,
859 F.2d 1396, 1397-98 (9th Cir. 1988). Even United States
v. Baron, upon which the dissent relies, affirmed on grounds
presented on appeal by the prosecution. Baron, 860 F.2d at
913.

   A party seeking to raise an issue must include that issue in
its brief, setting the issue forth in the brief’s “contentions
[along with] the reasons . . . , with citations to the authorities”
and the record. FED. R. APP. P. 28(a)(9)(A), (b). This the gov-
ernment completely fails to do. The brief mentions officer
safety only once, in its “Facts” section, where it reports that
Mendez was asked to sit on the curb during the stop (leaving
three small children alone in his car) because of officer safety.
It does not mention the subject again and does not refer even
once to officer safety in the “Argument” section of the brief.
Nor does it cite to any authority on the officer safety issue.
Indisputably, the government did not seek on appeal to justify
the questioning or the search on officer safety grounds. As a
result of the government’s failure to raise the issue, the defen-
dant did not have the opportunity to respond to the arguments
that the dissent now offers on the government’s behalf.

   It is likely that the government refrained from raising the
officer safety issue on appeal in part, at least, because it
believed that officer safety did not justify the questioning
here. At oral argument, the government acknowledged that its
entire case rose or fell on whether Mendez’s gang member-
ship and prior imprisonment created reasonable suspicion of
criminal activity sufficient to justify Det. Bracke’s additional
and unrelated questioning.21 In addition, the government’s
  21
    The discussion at oral argument included the following:
                        UNITED STATES v. MENDEZ                        18043
unwillingness to raise the issue is not surprising as the cir-
cumstances make it plain that the interrogation was not moti-
vated by safety concerns. When the officers took Mendez out
of his car and frisked him,22 they did not seek to discover
    The Court:              So why was it necessary, what was the total-
                            ity of the circumstances that justified the
                            further questioning about why were you in
                            prison and do you have a gun in the car?
      The Government: Well that came about first from asking him,
                            “Where are you from?” and instead of say-
                            ing “I am from Chicago or I am from Los
                            Angeles,” “I’m from the Latin Kings” which
                            is a suspicious answer in itself. They fol-
                            lowed up on that question or he actually fol-
                            lowed up and volunteered not only am I
                            from the Latin Kings but I’ve spent time in
                            prison . . . . So investigating that further line
                            of questioning, based on that new reasonable
                            suspicion . . . .
This exchange was shortly followed by:
      The Court:            Your position is that the issue in the case is
                            if a man has gang symbols on and he’s been
                            in prison, that gives you particularized sus-
                            picion?
      The Government: Yes, that’s what the district court found, that
                            the fact — yes, yes, that that is, that is the
                            position, yes your Honor, yes.
      The Court:            And if we decided that was not, those facts
                            did not give rise to particularized suspicion,
                            you would lose?
      The Government: I believe so. Yes.
   Although it is true, as the dissent notes, that, in response to a suggestion
originating with our dissenting colleague, government counsel made a
brief allusion to officer safety during the oral argument, the reference is
far from sufficient to resurrect the issue that it abandoned in its briefs,
especially given its reiteration of the issue that it acknowledged was
before the court.
   22
      Mendez does not challenge this frisk, so we do not consider whether
it could be justified by officer safety concerns. We note, however, that his
failure to challenge the frisk does not, as the dissent argues, amount to a
concession that the frisk is justified by officer safety concerns. Rather, it
is most likely due to the fact that nothing was found in the frisk and, as
a result, there is no need for Mendez to argue that the fruits of the frisk
should be suppressed.
18044              UNITED STATES v. MENDEZ
whether he had any weapons in his car. Instead, they seated
him on the curb and interrogated him about his gang member-
ship, tattoos, and other matters. Only later, in the course of
conducting the unlawful investigation, did they learn of his
prior conviction, several years before, on a weapons charge
and on the basis of that information ask him whether he was
currently committing a felony — felon in possession of a gun.
Thus, the context of the questioning clearly demonstrates its
investigatory nature. Given all these circumstances, a judg-
ment on the part of the government not to raise officer safety
on appeal would not be unreasonable. Moreover, even though
the defendant in his brief referred to the issue briefly, noting
that the government might choose to raise officer safety in its
answering brief, the government failed to do so. All of these
circumstances make it apparent to us that the government’s
choice was deliberate.

   We note that this is not an instance in which we are justi-
fied in deciding an issue not raised by the parties in order to
avoid incorrectly interpreting the law. We do not create any
incorrect precedent by refraining from reaching the officer
safety issue in this case. Nor do we create any intra- or inter-
circuit conflict. We simply preserve an issue for another day.

   [13] For the above reasons, we decline to consider the offi-
cer safety issue on this appeal. We need not decide here
whether we could, in our discretion, overlook the govern-
ment’s decision not to raise the issue before us. Given all of
the facts and circumstances we have described above, we sim-
ply determine that to the extent such discretion exists, this is
not an appropriate case in which to exercise it.

   We fully appreciate the importance of officer safety and
agree that officers should have the ability to take necessary
steps to protect themselves. For this reason, we note that even
were we to reach the question of officer safety on the merits,
we would be confronted with a number of questions similar
                   UNITED STATES v. MENDEZ                 18045
to those that required us to exclude the evidence under Part
A., supra.

                    III.   CONCLUSION

   We hold that, because the fact of gang membership is not
sufficient to generate a particularized, reasonable suspicion of
criminal activity, Det. Jaensson was not justified in expanding
his questioning of Mendez to topics beyond the scope of the
traffic stop. Even if the officers could also have considered
that Mendez had once served a prison sentence, this informa-
tion, either alone or in combination with the information
regarding gang membership, does not give rise to the requisite
type of particularized suspicion necessary to expand the scope
of the interrogation. The dissent suggests that we consider
affirming the district court on the alternative ground of officer
safety. We decline to do so, as that issue was not raised or
briefed before us by the government.

   [14] Thus, we conclude that Mendez’s Fourth Amendment
rights were violated when he was subjected to interrogation
by the officers that exceeded the scope of the traffic stop.
Accordingly, the handgun seized from the car must be sup-
pressed as the product of this unlawful questioning. See Wong
Sun v. United States, 371 U.S. 471, 487-88 (1963). We there-
fore reverse the district court’s denial of the motion to sup-
press, vacate the conviction, and remand for further
proceedings consistent with this opinion.

  VACATED and REMANDED.



TALLMAN, Circuit Judge, dissenting:

  Here we go again. The Supreme Court has told us repeat-
edly that the Fourth Amendment protects against unreason-
able searches and seizures. United States v. Arvizu, 534 U.S.
18046               UNITED STATES v. MENDEZ
266, 273 (2002); Ohio v. Robinette, 519 U.S. 33, 39 (1996);
Florida v. Jimeno, 500 U.S. 248, 250 (1991). It does not
declare inviolate the sanctity of a suspect’s personal security
when a police officer has reasonable concerns for his safety.
In Terry v. Ohio, 392 U.S. 1 (1968), the Court recognized that
an officer may take reasonable measures to thwart the ability
of a suspect deemed to be potentially armed and dangerous
from harming the officer or innocent bystanders. Id. at 23; see
also Michigan v. Long, 463 U.S. 1032, 1034, 1047 (1983);
United States v. Willis, 431 F.3d 709, 717 (9th Cir. 2005);
United States v. $109,179 in U.S. Currency, 228 F.3d 1080,
1086 (9th Cir. 2000); United States v. Portillo, 633 F.2d 1313,
1320 (9th Cir. 1980).

   The Supreme Court says we must look to the “totality of
the circumstances” in order to determine whether the officers’
actions were reasonable under the Fourth Amendment. Robi-
nette, 519 U.S. at 39 (stating that “the touchstone of the
Fourth Amendment is reasonableness” and “[r]easonableness
. . . is measured in objective terms by examining the totality
of the circumstances” (internal quotation marks and citation
omitted)). The Court unanimously rejected as “contrary to our
prior decisions” the “divide-and-conquer” technique
employed by the Ninth Circuit in United States v. Arvizu, 232
F.3d 1241 (9th Cir. 2000), rev’d, 534 U.S. at 268, 274, to
rebuff the officer’s reasonable suspicion. Yet, once again the
majority reverts to this discredited device to pick apart every
justification for the officers’ actions and declares unconstitu-
tional questions critical to an officer’s safety. In doing so, the
majority fails to view the evidence in the light most favorable
to the district court’s decision to uphold the seizure of the
weapon. See United States v. Harrington, 636 F.2d 1182,
1185 (9th Cir. 1980). I respectfully dissent.

                                I

   Terry tells us that we employ a two-pronged analysis to
field interviews: (1) is there reasonable suspicion that criminal
                        UNITED STATES v. MENDEZ                      18047
activity is afoot to justify further police inquiry, and (2) can
the officers articulate reasons to fear the suspect may be
armed, thereby justifying action to ensure the officer’s safety.
See 392 U.S. at 21-22, 27. Phoenix Gang Enforcement Detec-
tives Carl Jaensson and Jim Bracke were patrolling an area of
high gang activity.1 The stop occurred at night in a gang
neighborhood and Detective Jaensson immediately ordered
Mendez out of the vehicle and patted him down for weapons.
Mendez does not challenge the reason for this lawful investi-
gatory stop—he had failed to display a valid Arizona license
plate with a current registration tag. Nor does Mendez chal-
lenge the lawfulness of this pat-down frisk—the detectives’
testimony that they reasonably feared for their safety was
undisputed. It was during the pat-down that Detective Jaen-
sson first noticed a gang-related tattoo located on Mendez’s
left hand. Based on his eight years of experience as a gang-
enforcement detective, he readily recognized this tattoo as the
insignia of a well-known and violent street gang, the Latin
Kings.
  1
   During the motion to suppress hearing, defense counsel admitted to the
court that the officers had pulled Mendez over in a “gang neighborhood.”
The colloquy between the court and defense counsel went as follows:
      COURT: I don’t think - - I’m not sure that the Government even
      argues this, but if you’re on gang duty, as they were, in a gang
      neighborhood, as they were, and admittedly they make a traffic
      stop of this type, now they discover that the driver has a gang
      symbol, volunteers that he came from a gang, doesn’t that - -
      doesn’t that sequence entitle them to expand the scope further on
      the strength of those two points?
      DEFENSE COUNSEL: But expand the scope in what direction?
      . . . You identified the factors immediately, Judge. Th[e]se [are]
      gang officers patrolling a gang neighborhood, contending that
      they pulled Mr. Mendez over to investigate his lapsed registra-
      tion.
   In response to this colloquy, the prosecutor followed up by arguing that
the detectives’ questions were justified by a reasonable concern for their
own personal safety. See infra § III.
18048                  UNITED STATES v. MENDEZ
   Although he found no weapons on Mendez’s person,
Detective Jaensson did not permit him to return to his vehicle
at that time; rather, Detective Jaensson ordered Mendez to sit
on the curb while Detective Bracke returned to their police car
to run a computer search. When asked at the motion to sup-
press hearing why he ordered Mendez to sit on the curb,
Detective Jaensson answered, “For our safety . . . so that [he]
would have a harder time getting up and attacking us if that
was [sic] to happen.” Mendez does not challenge this deci-
sion.

   Detective Jaensson knew that the Latin Kings were a
Chicago-based gang; yet, Mendez had provided a California
identification card, and the car he was driving had an expired
temporary registration from Arizona. While awaiting the
results of Detective Bracke’s records search, Detective Jaen-
sson asked Mendez where he was from.2 Rather than respond-
ing with a specific location, Mendez told Detective Jaensson
that he was from the Latin Kings. Contrary to the majority’s
   2
     Mendez contends that the detectives were not justified in asking him
where he was from, and, although the majority does not hold as such, it
“doubt[s] that this question was related to the purpose of the stop.” Maj.
op. 18029. The Fourth Amendment surely does not prohibit such relevant
and innocuous questions when police are investigating a person operating
a vehicle in violation of the law and the circumstances show multiple state
contacts. The Supreme Court tells us that during even a routine traffic stop
an “officer may ask the detainee a moderate number of questions to deter-
mine his identity and to try to obtain information confirming or dispelling
the officer’s suspicions.” Berkemer v. McCarty, 468 U.S. 420, 439 (1984);
see also United States v. Hill, 195 F.3d 258, 268 (6th Cir. 1999) (holding
questions about a driver’s “purpose for traveling” were reasonably related
to a traffic stop for speeding). Any concern the majority may have over
the detectives’ subjective intent is misplaced and irrelevant. See Whren v.
United States, 517 U.S. 806, 812 (1996) (stating that, in United States v.
Villamonte-Marquez, 462 U.S. 579, 584 n.3 (1983), the Court “flatly dis-
missed the idea that an ulterior motive might serve to strip the agents of
their legal justification” in conducting an otherwise valid warrantless
search); United States v. Michael R., 90 F.3d 340, 346 (9th Cir. 1996)
(“Under Whren, [defendant] is precluded from challenging the traffic stop
based on [the officer’s] subjective intent.”).
                      UNITED STATES v. MENDEZ                       18049
position, the record does not suggest that Detective Jaensson
continued to “interrogate” or “question” Mendez about his
gang-related activity. Indeed, the majority cannot conclu-
sively state that any one question was unlawful because there
is no clear indication from the record as to how the conversa-
tion between Detective Jaensson and Mendez proceeded.
Detective Jaensson testified that he had asked Mendez to
show him the rest of his tattoos but that he could not recall
any specifics from their discussion about those tattoos, other
than Mendez telling him that he had left the Illinois gang in
“good standing” and that he was trying to make a life for him-
self now in Arizona.

   When Detective Bracke returned, he overheard Mendez tell
Detective Jaensson that he had spent eight years in an Illinois
prison. Detective Bracke then asked Mendez, “Why were you
in prison?”3 Once Mendez answered that he was in prison on
a weapons violation, Detective Bracke immediately followed
up with the question, “Do you have any weapons in your
car?”

   During the evidentiary hearing on the motion to suppress
the gun, Detective Jaensson was asked, “Why was it impor-
tant to inquire as to whether [Mendez] had a weapon once you
had received the information he had given you?” Detective
Jaensson gave a common-sense response—for officer safety:

      Basically, it’s again for our safety. When Mr.
      Mendez, if he’s released, if we issue him a citation
      and he’s upset, if he goes back to his vehicle and
      there’s a weapon there, we might have a problem
      with our safety.
  3
    Although the police report suggests that Mendez volunteered the infor-
mation as to why he was in prison, Detectives Jaensson and Bracke both
testified that Detective Bracke may have asked him directly. Because the
district court failed to resolve this factual discrepancy, and because the
detectives were justified in asking him this question for their own safety
in any event, I will assume that Mendez did not volunteer this information.
18050                UNITED STATES v. MENDEZ
Then, when asked by defense counsel whether the weapons-
related questions had anything to do with the purpose of the
initial traffic stop, Detective Jaensson unequivocally
responded, “Yes.” He explained:

      Because my policy is I’m going home at night, I
      want to make sure that me and my partner are going
      to be safe, and the people that we stop a lot of times
      will have guns so the bottom line for me is if they
      have a gun I want to know about it so that I am safe
      and my partner is safe.

Detective Jaensson’s undisputed testimony was that ensuring
officer safety was the sole reason Detective Bracke asked
Mendez if he had a weapon in his car.

   Only eight minutes elapsed from the initial stop to the
arrest of Mendez for unlawful possession of the firearm. Eight
minutes is hardly an unreasonable detention in violation of the
Fourth Amendment when there is no challenge to the legiti-
macy of the initial stop. Yet, the majority finds that safety-
related questions prompted by admissions volunteered by
Mendez were constitutionally impermissible.

                                   II

   The Court’s opinion seeks to pigeonhole the facts of this
case into the first prong of the Terry analysis—concerning
investigatory stops and limitations on questions related to the
purpose of those stops—and ignores any concern over officer
safety, undeniably a substantial concern for Detectives Jaen-
sson and Bracke and one which the Supreme Court has
repeatedly validated. See, e.g., Long, 463 U.S. at 1049. The
majority concludes that the detectives unlawfully expanded
the scope of the initial stop by asking Mendez (1) about his
gang-related tattoos, and (2) why he was in prison.4 The
  4
   I agree that Mendez waived his state law claim by failing to raise it
before the district court. Maj. op. 18027 n.9.
                    UNITED STATES v. MENDEZ                 18051
majority’s decision erroneously focuses on its belief that the
two factors—gang affiliation and former prison service—did
not provide particularized, objective factors suggesting that
Mendez was currently engaged in criminal activity. By doing
so, the majority entirely disregards the second prong of Terry
and an independent justification for the detectives’ actions:
prior gang affiliation and former prison service did give the
detectives a reasonable basis to fear for their safety, permit-
ting further inquiry.

   The majority relies heavily on our prior decision in United
States v. Chavez-Valenzuela, 268 F.3d 719 (9th Cir. 2001).
There, we held that nervous behavior on the part of a Terry
suspect detained for a traffic violation did not give the officer
reasonable, particularized suspicion to ask the suspect about
possible drug-related activity. Id. at 726. We stated that
“[q]uestions asked initially during a traffic stop must be rea-
sonably related to the justification for the stop,” id. at 725 n.4,
and an officer may expand the scope of questioning beyond
the stop’s initial purpose “only if he notices particularized,
objective factors arousing his suspicion” of criminal activity,
id. at 724. However, Chavez-Valenzuela is inapposite to this
situation because Detectives Jaensson and Bracke did not
expand the scope of the investigatory stop, and, while dili-
gently investigating the unchallenged reason for the stop, the
detectives learned facts about Mendez that caused them rea-
sonably to fear for their safety.

   The majority’s incongruous conclusion that Detective Jaen-
sson exceeded the limits of his constitutional authority by
eliciting information about Mendez’s tattoos is simply unsub-
stantiated by any Ninth Circuit or Supreme Court authority.
First and foremost, the facts that Mendez presented a Califor-
nia identification card rather than a valid driver’s license, was
driving a car with an expired Arizona temporary registration
tag, and said he was from the Latin Kings, which Detective
Jaensson knew to be a Chicago-based gang, is most certainly
relevant to the totality of the circumstances analysis. It was
18052                  UNITED STATES v. MENDEZ
reasonable for Detective Jaensson to ask Mendez about his
tattoos in order to elicit general information about his gang
activity and to try to discern what Mendez was doing in Phoe-
nix that night.

   The Fourth Amendment does not require reasonable suspi-
cion to be based solely on factors that directly indicate crimi-
nal behavior. Arvizu, 534 U.S. at 273-75; United States v.
Sokolow, 490 U.S. 1, 9 (1989) (“Any one of these factors is
not by itself proof of any illegal conduct and is quite consis-
tent with innocent travel. But we think taken together they
amount to reasonable suspicion.”); United States v. Michael
R., 90 F.3d 340, 346 (9th Cir. 1996) (same). Furthermore, the
lack of a valid registration also gives rise to a reasonable sus-
picion that the vehicle could have been stolen. United States
v. Fernandez, 18 F.3d 874, 879 (10th Cir. 1994) (“[The] lack
of a valid registration, license, bill of sale, or some other indi-
cia of proof to lawfully operate and possess the vehicle in
question . . . giv[es] rise to objectively reasonable suspicion
that the vehicle may be stolen.”).

   At the time of Detective Jaensson’s alleged “interrogation,”
Detective Jaensson knew that Mendez was driving a vehicle
without license plates and that he was a member of the Latin
Kings.5 These facts support a reasonable suspicion that the
vehicle may have been stolen. Cf. United States v. Thompson,
282 F.3d 673, 678 (9th Cir. 2002) (finding reasonable suspi-
cion that a vessel may have been stolen when the defendant
was unable to provide a valid registration, the vessel’s regis-
tration sticker had expired, and the defendant could not
remember the name of the vessel’s owner). Therefore,
because Detective Jaensson did have reasonable suspicion
that criminal activity could be afoot, any questions he might
have asked Mendez in order to elicit information regarding
  5
   Detective Jaensson testified that at the time of the traffic stop he “could
not see a temporary registration tag.” The record is unclear as to whether
he noticed the expired tag as he approached the car.
                    UNITED STATES v. MENDEZ                18053
possible gang activity—subsequent to Mendez’s volunteering
that he had served a prior prison term—were constitutionally
permissible. As such, Detective Jaensson lawfully obtained
the information regarding Mendez’s prior prison service.

   Moreover, asking the reason for the prison sentence was
not improper as the detectives understandably inquired further
for their own safety upon learning they had stopped a con-
victed felon. Under Terry, when an officer has a reasonable
basis to fear for his or her safety, the Fourth Amendment does
not “deny th[at] officer the power to take necessary measures
to determine whether the person is in fact carrying a weapon
and to neutralize the threat of physical harm.” 392 U.S. at 24.
The issue then becomes “whether a reasonably prudent man
in the circumstances would be warranted in the belief that his
safety or that of others was in danger.” Id. at 27.

   If an officer has a reasonable basis to fear for his safety, he
may ask questions to elicit information in an attempt to deter-
mine whether the suspect may be armed and dangerous. Wil-
lis, 431 F.3d at 717. In Willis, the officer watched as the
suspect made a succession of rapid turns, and stopped in front
of an apartment building in a high-crime area of Las Vegas.
Id. at 712. After the officer ran a check on the suspect’s
license plate, he learned that “the car was listed as a ‘suspi-
cious vehicle’ and that there was a National Crime Informa-
tion Center . . . missing person’s report or ‘hit’ associated
with the license plate.” Id. The suspect then returned to his
car, made an illegal U-turn, and parked in front of another
apartment only one or two blocks away; at this point an offi-
cer pulled the suspect over. Id. After the suspect nervously
exited his car, the officer ordered him to go to the front of the
vehicle and asked, “Do you have anything on you I should
know about?” Id. The suspect admitted to having a gun in his
jacket pocket, id., and we upheld the validity of the investiga-
tory stop and the officer’s questions, id. at 715, 717. We
stated that “[o]nce the police stopped [the suspect], they
could, within reason, search the area and question [him] about
18054                  UNITED STATES v. MENDEZ
weapons for their own safety.” Id. at 717. We also noted that
“[the officer] did not take more extreme measures, but simply
asked [the suspect] a question to ensure the officers’ personal
safety.” Id.

   Even assuming arguendo that gang affiliation and former
prison service did not present particularized, objective factors
sufficient to raise a reasonable suspicion of current criminal
activity in order to justify the question, “Why were you in
prison?” knowledge of Mendez’s gang membership and prior
weapons conviction surely gave Detectives Jaensson and
Bracke a reasonable basis to fear for their safety. Given the
time of night and the location of the stop, Mendez concedes
that Detectives Jaensson and Bracke acted reasonably by
ordering him out of the vehicle and immediately patting him
down for weapons. The reasonable fear that caused the detec-
tives to take that approach did not dissipate once they learned
that Mendez was a member of the Latin Kings. See United
States v. Barboza, 412 F.3d 15, 15-16 (1st Cir. 2005) (uphold-
ing the legality of a protective search when the officers
encountered a “suspected gang member[ ] on a street . . .
known for gang violence” and had reason to believe that the
suspect was a “gang-affiliated individual who routinely car-
ried a firearm”); Michael R., 90 F.3d at 346 (“[T]he fact that
the young men had haircuts that were characteristic of gang
members has evidentiary significance under the totality of the
circumstances analysis.”).6 It was certainly not diminished
   6
     The majority’s reliance on Spivey v. Rocha, 194 F.3d 971 (9th Cir.
1999), to support its position that gang affiliation does not raise reasonable
suspicion as to whether a suspect may be carrying a weapon is misplaced.
There, while reviewing a state court conviction, we held that the trial
court’s failure to admit “evidence of [the witness’s] gang affiliation to bol-
ster [the defendant’s] assertion that he armed himself in self-defense” was
not constitutional error. Id. at 977-78. We reasoned that “the tendency of
members of a gang to carry weapons does not lead reasonably to any
inference as to whether a gang member was armed on a given occasion,”
and, furthermore, any probative value it may have “was outweighed by the
prejudicial effect of admitting gang affiliation.” Id. at 978 (internal quota-
                       UNITED STATES v. MENDEZ                        18055
when Mendez volunteered that he was an ex-convict, having
previously served an eight-year prison term in Illinois.

   As the Fourth Circuit stated in United States v. Holmes, 376
F.3d 270 (2004), “reasonable suspicion of a suspect’s danger-
ousness need not be based solely on activities observed by the
police during or just before the relevant police encounter, but
can be based on the suspect’s commission of violent crimes
in the past—especially when those crimes indicate a high
likelihood that a suspect will be ‘armed and dangerous’ when
encountered in the future.”7 Id. at 278; see also $109,179 in
U.S. Currency, 228 F.3d at 1086 (an officer can assume “from
the nature of the offense contemplated” that a suspect may be
armed and dangerous). This information can only have
heightened their suspicion that Mendez might have a weapon
in his car, and the Fourth Amendment’s reasonableness
requirement demands nothing more. After hearing Mendez
admit to gang affiliation and a felony conviction for which he
had served eight years in prison, the detectives “could . . .
question [Mendez] about weapons for their own safety.” See
Willis, 431 F.3d at 717.

tion marks omitted). Equating the admittance of evidence for the purpose
of trial to the circumstances faced by Detectives Jaensson and Bracke in
the field—when their personal safety was at stake—is perverse. See
United States v. Feliciano, 45 F.3d 1070, 1074 (7th Cir. 1995) (recogniz-
ing that while gang association has “doubtful evidentiary value” it none-
theless is “a permissible component of the articulable suspicion required
for a Terry stop”). Under the totality of the circumstances, it was reason-
able for the detectives to fear for their safety. In those circumstances, gang
affiliation coupled with an eight-year prison term on a weapons charge
supports a reasonable suspicion that a particular individual may be armed
and dangerous.
   7
     I note here that Detective Bracke merely asked Mendez why he was in
prison, suggesting that Detective Bracke’s intent was not to investigate
current criminal activity, but to gauge the safety threat posed by Mendez
to the detectives based on their understandable desire to know more about
the formerly imprisoned person with whom they were dealing.
18056              UNITED STATES v. MENDEZ
   Detective Bracke did not ask Mendez these questions to
investigate ongoing criminal activity; instead, he asked these
questions in order to determine whether there was a reason to
subject Mendez to a more intrusive safety search—a protec-
tive sweep of his vehicle. See Barboza, 412 F.3d at 16 (“The
purpose of a protective search in the absence of probable
cause is not to discover evidence of a crime, but to neutralize
the threat of physical harm to police officers and others.”).
When an officer believes that a suspect may be armed and
dangerous, it is not unreasonable for that officer to “tak[e]
preventive measures to ensure that there were no other weap-
ons within [the suspect’s] immediate grasp before permitting
him to reenter his automobile.” Long, 463 U.S. at 1051. As
recognized by the Seventh Circuit in United States v. Rai-
none, 586 F.2d 1132 (7th Cir. 1978), there are inherent differ-
ences between a Terry stop executed on the sidewalk and one
executed while the suspect is in an automobile:

    Obviously in a sidewalk encounter with a pedestrian,
    such as occurred in Terry, the officer’s need to pro-
    tect himself from dangerous weapons is fully satis-
    fied by a pat-down of outer clothing of the suspect.
    However, where the suspect is driving an automo-
    bile, a pat-down of the outer clothing may not be
    sufficient to assure the safety of the police officer. In
    those cases there is the real possibility that a weapon
    may have been secreted in a part of the automobile
    readily accessible to the suspect. This is particularly
    true where the suspect remains in the car, but is also
    true even where the suspect has been removed from
    the car. In the latter instance there is still a risk that
    the suspect may break away or that he may have a
    motive to kill the officer even after returning to his
    car. Thus, it is clear that [under] the rationale of
    Terry the protection of the investigating officer and
    others nearby permits the officer to make a search of
    the automobile, limited to what is minimally neces-
                   UNITED STATES v. MENDEZ               18057
    sary to uncover weapons to which the suspect will
    have easy access.

Id. at 1134-35 (footnotes omitted), cited with approval in
Long, 463 U.S. at 1051 (stating that it is not impossible for
a “Terry suspect . . . [to] break away from police control and
retrieve a weapon from his automobile”); see also United
States v. Wilkerson, 598 F.2d 621, 625 (D.C. Cir. 1978) (“It
takes little imagination to realize that an armed suspect might
hide his weapon in a car before getting out in response to a
police order.”), cited with approval in Portillo, 633 F.2d at
1320.

   For these reasons, the Supreme Court has upheld the right
of police officers to conduct a limited search of the passenger
compartment of an automobile when “the police officer pos-
sesses a reasonable belief based on ‘specific and articulable
facts which, taken together with the rational inferences from
those facts, reasonably warrant’ the officers in believing that
the suspect is dangerous and the suspect may gain immediate
control over weapons.” Long, 463 U.S. at 1049-50 (citing
Terry, 392 U.S. at 21). Although Detective Jaensson had
already patted Mendez down for weapons, he still posed a
threat to the detectives. See Long, 463 U.S. at 1051; Wilker-
son, 598 F.2d at 625; Rainone, 586 F.2d at 1134-35. His
answers to Detective Jaensson’s questions—that he was a
member of the Latin Kings and that he had served an eight-
year prison term—failed to dispel the detectives’ reasonable
suspicion that Mendez might pose a danger to the detectives.
Cf. $109,179 in U.S. Currency, 228 F.3d at 1086 (finding a
Terry pat-down to be reasonable because the suspect failed to
alleviate the officer’s reasonable belief that the suspect was
armed and dangerous during the officer’s initial questioning).

   Because it was entirely feasible that Mendez may have con-
cealed his weapon in his car before the detectives approached
his vehicle, and because it was always possible for Mendez to
break away from the detectives during the investigatory stop
18058                  UNITED STATES v. MENDEZ
for fear that his arrest was imminent or to retaliate upon the
issuance of a citation, Mendez’s threat to the safety of Detec-
tives Jaensson and Bracke never abated. Given the totality of
the circumstances, and that “investigative detentions involv-
ing suspects in vehicles are especially fraught with danger to
police officers,” Long, 463 U.S. at 1047, Detective Bracke’s
understandable desire to protect himself and his partner so
they could go home at the end of their shift was nothing but
reasonable.8

                                     III

   The majority’s refusal to address the officer safety issue
makes no sense in light of the record below. Rather than ana-
lyzing this case under both prongs of law announced in Terry
and applying the correct analysis dictated in Arvizu, the
majority seizes upon a verbal misstep by the government
attorney. The approach employed by the majority—limiting
its reasonableness analysis to only one justification—is not
just another example of what the Supreme Court has unani-
mously condemned as “divide-and-conquer,” but an even
more egregious approach of “divide, conquer, and ignore.”

   Contrary to the majority’s position, the government did
argue that the detectives’ questions were justified by concerns
for officer safety. During oral argument, the government
stated, “There was an officer safety concern here . . . .” How-
ever, before being allowed to finish the answer, the govern-
ment was pressed by the court with questions regarding
  8
    Because the detectives’ actions were justified and reasonable,
Mendez’s argument that the detectives unlawfully prolonged the stop is
meritless. See United States v. Sharpe, 470 U.S. 675, 686 (1985) (“In
assessing whether a detention is too long in duration to be justified as an
investigative stop, . . . it [is] appropriate to examine whether the police
diligently pursued a means of investigation that was likely to confirm or
dispel their suspicions quickly.”). Detectives Jaensson and Bracke were
diligent in their investigation, as evidenced by the fact that only eight min-
utes had passed between the initial stop and Mendez’s arrest.
                   UNITED STATES v. MENDEZ                18059
whether gang affiliation and former prison service were suffi-
cient to create particularized, objective factors of current
criminal activity. In response, the government conceded that
those facts would have been the sole basis for the detectives’
decision to expand the scope of the investigatory stop; how-
ever, the government never conceded that a reasonable suspi-
cion of current criminal activity was the sole justification for
the detectives’ questions. It did try to articulate another
justification—officer safety—before being interrupted by
questions from the court.

   Moreover, “when reviewing a motion to suppress, the court
may affirm on any ground fairly supported by the record.”
United States v. Baron, 860 F.2d 911, 917 (9th Cir. 1988) (cit-
ing United States v. Smith, 790 F.2d 789, 792 (9th Cir. 1986)).
During the motion to suppress hearing, the government made
the following argument:

       When we think of Terry we typically think of do
    the officers have reasonable suspicion to investigate?
    But there’s more to Terry than that. There is also the
    officer safety issue.

       ....

       The measures taken here to ensure that Mr.
    Mendez was not armed and did not have access to a
    weapon were clearly reasonable. It [sic] involved
    questioning, do you have a weapon in the vehicle,
    after the officers had specific articulable reasons for
    asking that question.

The Government also raised this argument in its opposition to
the motion to suppress. The district court believed that gang
affiliation and former prison service were sufficient to raise
particularized suspicion of current criminal activity, and,
therefore, it did not rule on the officer safety issue. However,
this theory is clearly supported by the evidentiary record, was
18060              UNITED STATES v. MENDEZ
expressly argued before the district court, and we are obli-
gated to address it now. We should not be so quick to con-
clude that the detectives’ actions were unconstitutional when
it is evident from the record that they acted reasonably to pro-
tect themselves under the totality of the circumstances.

                              IV

   The Fourth Amendment does not require police officers to
take unnecessary risks in the performance of their duties.
Constraining an officer’s ability to make further inquiry into
a Terry suspect’s potential dangerousness endangers the offi-
cer, his partner, and innocent bystanders, and contravenes
established Supreme Court caselaw authorizing the use of rea-
sonable protective measures to ensure officer safety. Two
experienced gang-enforcement detectives were confronting a
gang member, in a gang neighborhood, who admitted to serv-
ing an eight-year prison term on a weapons charge. Faced
with such a situation, they made a reasonable decision to
make further inquiry into whether Mendez had a gun in his
car. The questions they posed were not overly intrusive and
were directly related to their legitimate safety concern.

  I respectfully dissent.
