(Slip Opinion)               OCTOBER TERM, 2014                                       1

                                        Syllabus

          NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
        being done in connection with this case, at the time the opinion is issued.
        The syllabus constitutes no part of the opinion of the Court but has been
        prepared by the Reporter of Decisions for the convenience of the reader.
        See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                        Syllabus

                  RODRIGUEZ v. UNITED STATES

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                 THE EIGHTH CIRCUIT

    No. 13–9972. Argued January 21, 2015—Decided April 21, 2015
Officer Struble, a K–9 officer, stopped petitioner Rodriguez for driving
  on a highway shoulder, a violation of Nebraska law. After Struble at-
  tended to everything relating to the stop, including, inter alia, check-
  ing the driver’s licenses of Rodriguez and his passenger and issuing a
  warning for the traffic offense, he asked Rodriguez for permission to
  walk his dog around the vehicle. When Rodriguez refused, Struble
  detained him until a second officer arrived. Struble then retrieved
  his dog, who alerted to the presence of drugs in the vehicle. The en-
  suing search revealed methamphetamine. Seven or eight minutes
  elapsed from the time Struble issued the written warning until the
  dog alerted.
     Rodriguez was indicted on federal drug charges. He moved to sup-
  press the evidence seized from the vehicle on the ground, among oth-
  ers, that Struble had prolonged the traffic stop without reasonable
  suspicion in order to conduct the dog sniff. The Magistrate Judge
  recommended denial of the motion. He found no reasonable suspicion
  supporting detention once Struble issued the written warning. Un-
  der Eighth Circuit precedent, however, he concluded that prolonging
  the stop by “seven to eight minutes” for the dog sniff was only a de
  minimis intrusion on Rodriguez’s Fourth Amendment rights and was
  for that reason permissible. The District Court then denied the mo-
  tion to suppress. Rodriguez entered a conditional guilty plea and was
  sentenced to five years in prison. The Eighth Circuit affirmed. Not-
  ing that the seven or eight minute delay was an acceptable “de mini-
  mis intrusion on Rodriguez’s personal liberty,” the court declined to
  reach the question whether Struble had reasonable suspicion to con-
  tinue Rodriguez’s detention after issuing the written warning.
Held:
2                    RODRIGUEZ v. UNITED STATES

                                   Syllabus

         1. Absent reasonable suspicion, police extension of a traffic stop
    in order to conduct a dog sniff violates the Constitution’s shield
    against unreasonable seizures.
       A routine traffic stop is more like a brief stop under Terry v. Ohio,
    392 U. S. 1, than an arrest, see, e.g., Arizona v. Johnson, 555 U. S.
    323, 330. Its tolerable duration is determined by the seizure’s “mis-
    sion,” which is to address the traffic violation that warranted the
    stop, Illinois v. Caballes, 543 U. S. 405, 407 and attend to related
    safety concerns. Authority for the seizure ends when tasks tied to
    the traffic infraction are—or reasonably should have been—
    completed. The Fourth Amendment may tolerate certain unrelated
    investigations that do not lengthen the roadside detention, Johnson,
    555 U. S., at 327–328 (questioning); Caballes, 543 U. S., at 406, 408
    (dog sniff), but a traffic stop “become[s] unlawful if it is prolonged be-
    yond the time reasonably required to complete th[e] mission” of issu-
    ing a warning ticket, id., at 407.
       Beyond determining whether to issue a traffic ticket, an officer’s
    mission during a traffic stop typically includes checking the driver’s
    license, determining whether there are outstanding warrants against
    the driver, and inspecting the automobile’s registration and proof of
    insurance. These checks serve the same objective as enforcement of
    the traffic code: ensuring that vehicles on the road are operated safe-
    ly and responsibly. See Delaware v. Prouse, 440 U. S. 648, 658–659.
    Lacking the same close connection to roadway safety as the ordinary
    inquiries, a dog sniff is not fairly characterized as part of the officer’s
    traffic mission.
       In concluding that the de minimis intrusion here could be offset by
    the Government’s interest in stopping the flow of illegal drugs, the
    Eighth Circuit relied on Pennsylvania v. Mimms, 434 U. S. 106. The
    Court reasoned in Mimms that the government’s “legitimate and
    weighty” interest in officer safety outweighed the “de minimis” addi-
    tional intrusion of requiring a driver, lawfully stopped, to exit a vehi-
    cle, id., at 110–111. The officer-safety interest recognized in Mimms,
    however, stemmed from the danger to the officer associated with the
    traffic stop itself. On-scene investigation into other crimes, in con-
    trast, detours from the officer’s traffic-control mission and therefore
    gains no support from Mimms.
       The Government’s argument that an officer who completes all traf-
    fic-related tasks expeditiously should earn extra time to pursue an
    unrelated criminal investigation is unpersuasive, for a traffic stop
    “prolonged beyond” the time in fact needed for the officer to complete
    his traffic-based inquiries is “unlawful,” Caballes, 543 U. S., at 407.
    The critical question is not whether the dog sniff occurs before or af-
    ter the officer issues a ticket, but whether conducting the sniff adds
                     Cite as: 575 U. S. ____ (2015)                     3

                                Syllabus

  time to the stop. Pp. 5–8.
       2. The determination adopted by the District Court that deten-
  tion for the dog sniff was not independently supported by individual-
  ized suspicion was not reviewed by the Eighth Circuit. That question
  therefore remains open for consideration on remand. P. 9.
741 F. 3d 905, vacated and remanded.

  GINSBURG, J., delivered the opinion of the Court, in which ROBERTS,
C. J., and SCALIA, BREYER, SOTOMAYOR, and KAGAN, JJ., joined. KEN-
NEDY, J., filed a dissenting opinion. THOMAS, J., filed a dissenting opin-
ion, in which ALITO, J., joined, and in which KENNEDY, J., joined as to
all but Part III. ALITO, J., filed a dissenting opinion.
                        Cite as: 575 U. S. ____ (2015)                              1

                             Opinion of the Court

     NOTICE: This opinion is subject to formal revision before publication in the
     preliminary print of the United States Reports. Readers are requested to
     notify the Reporter of Decisions, Supreme Court of the United States, Wash­
     ington, D. C. 20543, of any typographical or other formal errors, in order
     that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                   _________________

                                   No. 13–9972
                                   _________________


          DENNYS RODRIGUEZ, PETITIONER v.

                  UNITED STATES

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE EIGHTH CIRCUIT

                                 [April 21, 2015] 


   JUSTICE GINSBURG delivered the opinion of the Court.
   In Illinois v. Caballes, 543 U. S. 405 (2005), this Court
held that a dog sniff conducted during a lawful traffic stop
does not violate the Fourth Amendment’s proscription of
unreasonable seizures. This case presents the question
whether the Fourth Amendment tolerates a dog sniff
conducted after completion of a traffic stop. We hold that
a police stop exceeding the time needed to handle the
matter for which the stop was made violates the Constitu­
tion’s shield against unreasonable seizures. A seizure
justified only by a police-observed traffic violation, there­
fore, “become[s] unlawful if it is prolonged beyond the time
reasonably required to complete th[e] mission” of issuing a
ticket for the violation. Id., at 407. The Court so recog­
nized in Caballes, and we adhere to the line drawn in that
decision.
                            I
  Just after midnight on March 27, 2012, police officer
Morgan Struble observed a Mercury Mountaineer veer
slowly onto the shoulder of Nebraska State Highway 275
for one or two seconds and then jerk back onto the road.
2               RODRIGUEZ v. UNITED STATES

                      Opinion of the Court

Nebraska law prohibits driving on highway shoulders, see
Neb. Rev. Stat. §60–6,142 (2010), and on that basis, Stru­
ble pulled the Mountaineer over at 12:06 a.m. Struble is a
K–9 officer with the Valley Police Department in Ne­
braska, and his dog Floyd was in his patrol car that night.
Two men were in the Mountaineer: the driver, Dennys
Rodriguez, and a front-seat passenger, Scott Pollman.
   Struble approached the Mountaineer on the passenger’s
side. After Rodriguez identified himself, Struble asked
him why he had driven onto the shoulder. Rodriguez
replied that he had swerved to avoid a pothole. Struble
then gathered Rodriguez’s license, registration, and proof
of insurance, and asked Rodriguez to accompany him to
the patrol car. Rodriguez asked if he was required to do
so, and Struble answered that he was not. Rodriguez
decided to wait in his own vehicle.
   After running a records check on Rodriguez, Struble
returned to the Mountaineer. Struble asked passenger
Pollman for his driver’s license and began to question him
about where the two men were coming from and where
they were going. Pollman replied that they had traveled
to Omaha, Nebraska, to look at a Ford Mustang that was
for sale and that they were returning to Norfolk, Ne­
braska. Struble returned again to his patrol car, where he
completed a records check on Pollman, and called for a
second officer. Struble then began writing a warning
ticket for Rodriguez for driving on the shoulder of the
road.
   Struble returned to Rodriguez’s vehicle a third time to
issue the written warning. By 12:27 or 12:28 a.m., Struble
had finished explaining the warning to Rodriguez, and
had given back to Rodriguez and Pollman the documents
obtained from them. As Struble later testified, at that
point, Rodriguez and Pollman “had all their documents
back and a copy of the written warning. I got all the
reason[s] for the stop out of the way[,] . . . took care of all
                  Cite as: 575 U. S. ____ (2015)            3

                      Opinion of the Court

the business.” App. 70.
  Nevertheless, Struble did not consider Rodriguez “free
to leave.” Id., at 69–70. Although justification for the
traffic stop was “out of the way,” id., at 70, Struble asked
for permission to walk his dog around Rodriguez’s vehicle.
Rodriguez said no. Struble then instructed Rodriguez to
turn off the ignition, exit the vehicle, and stand in front of
the patrol car to wait for the second officer. Rodriguez
complied. At 12:33 a.m., a deputy sheriff arrived. Struble
retrieved his dog and led him twice around the Moun­
taineer. The dog alerted to the presence of drugs halfway
through Struble’s second pass. All told, seven or eight
minutes had elapsed from the time Struble issued the
written warning until the dog indicated the presence of
drugs. A search of the vehicle revealed a large bag of
methamphetamine.
  Rodriguez was indicted in the United States District
Court for the District of Nebraska on one count of posses­
sion with intent to distribute 50 grams or more of meth­
amphetamine, in violation of 21 U. S. C. §§841(a)(1) and
(b)(1). He moved to suppress the evidence seized from his
car on the ground, among others, that Struble had pro­
longed the traffic stop without reasonable suspicion in
order to conduct the dog sniff.
  After receiving evidence, a Magistrate Judge recom­
mended that the motion be denied. The Magistrate Judge
found no probable cause to search the vehicle independent
of the dog alert. App. 100 (apart from “information given
by the dog,” “Officer Struble had [no]thing other than a
rather large hunch”). He further found that no reasonable
suspicion supported the detention once Struble issued the
written warning. He concluded, however, that under
Eighth Circuit precedent, extension of the stop by “seven
to eight minutes” for the dog sniff was only a de minimis
intrusion on Rodriguez’s Fourth Amendment rights and
was therefore permissible.
4              RODRIGUEZ v. UNITED STATES

                      Opinion of the Court

   The District Court adopted the Magistrate Judge’s
factual findings and legal conclusions and denied Rodri­
guez’s motion to suppress. The court noted that, in the
Eighth Circuit, “dog sniffs that occur within a short time
following the completion of a traffic stop are not constitu­
tionally prohibited if they constitute only de minimis
intrusions.” App. 114 (quoting United States v. Alexander,
448 F. 3d 1014, 1016 (CA8 2006)). The court thus agreed
with the Magistrate Judge that the “7 to 10 minutes”
added to the stop by the dog sniff “was not of constitu­
tional significance.” App. 114. Impelled by that decision,
Rodriguez entered a conditional guilty plea and was sen­
tenced to five years in prison.
   The Eighth Circuit affirmed. The “seven- or eight-
minute delay” in this case, the opinion noted, resembled
delays that the court had previously ranked as permissi­
ble. 741 F. 3d 905, 907 (2014). The Court of Appeals thus
ruled that the delay here constituted an acceptable “de
minimis intrusion on Rodriguez’s personal liberty.” Id., at
908. Given that ruling, the court declined to reach the
question whether Struble had reasonable suspicion to
continue Rodriguez’s detention after issuing the written
warning.
   We granted certiorari to resolve a division among lower
courts on the question whether police routinely may ex­
tend an otherwise-completed traffic stop, absent reason­
able suspicion, in order to conduct a dog sniff. 573 U. S. ___
(2014). Compare, e.g., United States v. Morgan, 270 F. 3d
625, 632 (CA8 2001) (postcompletion delay of “well under
ten minutes” permissible), with, e.g., State v. Baker, 2010
UT 18, ¶13, 229 P. 3d 650, 658 (2010) (“[W]ithout addi­
tional reasonable suspicion, the officer must allow the
seized person to depart once the purpose of the stop has
concluded.”).
                  Cite as: 575 U. S. ____ (2015)              5

                      Opinion of the Court

                                II
   A seizure for a traffic violation justifies a police investi­
gation of that violation. “[A] relatively brief encounter,” a
routine traffic stop is “more analogous to a so-called ‘Terry
stop’ . . . than to a formal arrest.” Knowles v. Iowa, 525
U. S. 113, 117 (1998) (quoting Berkemer v. McCarty, 468
U. S. 420, 439 (1984), in turn citing Terry v. Ohio, 392
U. S. 1 (1968)). See also Arizona v. Johnson, 555 U. S.
323, 330 (2009). Like a Terry stop, the tolerable duration
of police inquiries in the traffic-stop context is determined
by the seizure’s “mission”—to address the traffic violation
that warranted the stop, Caballes, 543 U. S., at 407, and
attend to related safety concerns, infra, at 6–7. See also
United States v. Sharpe, 470 U. S. 675, 685 (1985); Florida
v. Royer, 460 U. S. 491, 500 (1983) (plurality opinion)
(“The scope of the detention must be carefully tailored to
its underlying justification.”). Because addressing the
infraction is the purpose of the stop, it may “last no longer
than is necessary to effectuate th[at] purpose.” Ibid. See
also Caballes, 543 U. S., at 407. Authority for the seizure
thus ends when tasks tied to the traffic infraction are—or
reasonably should have been—completed. See Sharpe,
470 U. S., at 686 (in determining the reasonable duration
of a stop, “it [is] appropriate to examine whether the police
diligently pursued [the] investigation”).
   Our decisions in Caballes and Johnson heed these con­
straints. In both cases, we concluded that the Fourth
Amendment tolerated certain unrelated investigations
that did not lengthen the roadside detention. Johnson,
555 U. S., at 327–328 (questioning); Caballes, 543 U. S., at
406, 408 (dog sniff). In Caballes, however, we cautioned
that a traffic stop “can become unlawful if it is prolonged
beyond the time reasonably required to complete th[e]
mission” of issuing a warning ticket. 543 U. S., at 407.
And we repeated that admonition in Johnson: The seizure
remains lawful only “so long as [unrelated] inquiries do
6              RODRIGUEZ v. UNITED STATES

                     Opinion of the Court

not measurably extend the duration of the stop.” 555
U. S., at 333. See also Muehler v. Mena, 544 U. S. 93, 101
(2005) (because unrelated inquiries did not “exten[d] the
time [petitioner] was detained[,] . . . no additional Fourth
Amendment justification . . . was required”). An officer, in
other words, may conduct certain unrelated checks during
an otherwise lawful traffic stop. But contrary to JUSTICE
ALITO’s suggestion, post, at 4, n. 2, he may not do so in a
way that prolongs the stop, absent the reasonable suspi­
cion ordinarily demanded to justify detaining an individ­
ual. But see post, at 1–2 (ALITO, J., dissenting) (premising
opinion on the dissent’s own finding of “reasonable suspi­
cion,” although the District Court reached the opposite
conclusion, and the Court of Appeals declined to consider
the issue).
  Beyond determining whether to issue a traffic ticket, an
officer’s mission includes “ordinary inquiries incident to
[the traffic] stop.” Caballes, 543 U. S., at 408. Typically
such inquiries involve checking the driver’s license, de­
termining whether there are outstanding warrants
against the driver, and inspecting the automobile’s regis­
tration and proof of insurance. See Delaware v. Prouse,
440 U. S. 648, 658–660 (1979). See also 4 W. LaFave,
Search and Seizure §9.3(c), pp. 507–517 (5th ed. 2012).
These checks serve the same objective as enforcement of
the traffic code: ensuring that vehicles on the road are
operated safely and responsibly. See Prouse, 440 U. S., at
658–659; LaFave, Search and Seizure §9.3(c), at 516 (A
“warrant check makes it possible to determine whether
the apparent traffic violator is wanted for one or more
previous traffic offenses.”).
   A dog sniff, by contrast, is a measure aimed at “de­
tect[ing] evidence of ordinary criminal wrongdoing.”
Indianapolis v. Edmond, 531 U. S. 32, 40–41 (2000). See
also Florida v. Jardines, 569 U. S. 1, ___–___ (2013) (slip
op., at 7–8). Candidly, the Government acknowledged at
                 Cite as: 575 U. S. ____ (2015)            7

                     Opinion of the Court

oral argument that a dog sniff, unlike the routine
measures just mentioned, is not an ordinary incident of a
traffic stop. See Tr. of Oral Arg. 33. Lacking the same
close connection to roadway safety as the ordinary inquir­
ies, a dog sniff is not fairly characterized as part of the
officer’s traffic mission.
   In advancing its de minimis rule, the Eighth Circuit
relied heavily on our decision in Pennsylvania v. Mimms,
434 U. S. 106 (1977) (per curiam). See United States v.
$404,905.00 in U. S. Currency, 182 F. 3d 643, 649 (CA8
1999). In Mimms, we reasoned that the government’s
“legitimate and weighty” interest in officer safety out­
weighs the “de minimis” additional intrusion of requiring
a driver, already lawfully stopped, to exit the vehicle. 434
U. S., at 110–111. See also Maryland v. Wilson, 519 U. S.
408, 413–415 (1997) (passengers may be required to exit
vehicle stopped for traffic violation). The Eighth Circuit,
echoed in JUSTICE THOMAS’s dissent, believed that the
imposition here similarly could be offset by the Govern­
ment’s “strong interest in interdicting the flow of illegal
drugs along the nation’s highways.” $404,905.00 in U. S.
Currency, 182 F. 3d, at 649; see post, at 9.
   Unlike a general interest in criminal enforcement,
however, the government’s officer safety interest stems
from the mission of the stop itself. Traffic stops are “espe­
cially fraught with danger to police officers,” Johnson, 555
U. S., at 330 (internal quotation marks omitted), so an
officer may need to take certain negligibly burdensome
precautions in order to complete his mission safely. Cf.
United States v. Holt, 264 F. 3d 1215, 1221–1222 (CA10
2001) (en banc) (recognizing officer safety justification for
criminal record and outstanding warrant checks), abro­
gated on other grounds as recognized in United States v.
Stewart, 473 F. 3d 1265, 1269 (CA10 2007). On-scene
investigation into other crimes, however, detours from
that mission. See supra, at 6–7. So too do safety precau­
8              RODRIGUEZ v. UNITED STATES

                      Opinion of the Court

tions taken in order to facilitate such detours. But cf. post,
at 2–3 (ALITO, J., dissenting). Thus, even assuming that
the imposition here was no more intrusive than the exit
order in Mimms, the dog sniff could not be justified on the
same basis. Highway and officer safety are interests
different in kind from the Government’s endeavor to de­
tect crime in general or drug trafficking in particular.
   The Government argues that an officer may “incremen­
tal[ly]” prolong a stop to conduct a dog sniff so long as the
officer is reasonably diligent in pursuing the traffic-related
purpose of the stop, and the overall duration of the stop
remains reasonable in relation to the duration of other
traffic stops involving similar circumstances. Brief for
United States 36–39. The Government’s argument, in
effect, is that by completing all traffic-related tasks expe­
ditiously, an officer can earn bonus time to pursue an
unrelated criminal investigation. See also post, at 2–5
(THOMAS, J., dissenting) (embracing the Government’s
argument). The reasonableness of a seizure, however,
depends on what the police in fact do. See Knowles, 525
U. S., at 115–117.       In this regard, the Government
acknowledges that “an officer always has to be reasonably
diligent.” Tr. of Oral Arg. 49. How could diligence be
gauged other than by noting what the officer actually did
and how he did it? If an officer can complete traffic-based
inquiries expeditiously, then that is the amount of “time
reasonably required to complete [the stop’s] mission.”
Caballes, 543 U. S., at 407. As we said in Caballes and
reiterate today, a traffic stop “prolonged beyond” that
point is “unlawful.” Ibid. The critical question, then, is
not whether the dog sniff occurs before or after the officer
issues a ticket, as JUSTICE ALITO supposes, post, at 2–4,
but whether conducting the sniff “prolongs”—i.e., adds
time to—“the stop,” supra, at 6.
                 Cite as: 575 U. S. ____ (2015)           9

                     Opinion of the Court

                             III
  The Magistrate Judge found that detention for the dog
sniff in this case was not independently supported by
individualized suspicion, see App. 100, and the District
Court adopted the Magistrate Judge’s findings, see id., at
112–113. The Court of Appeals, however, did not review
that determination. But see post, at 1, 10–12 (THOMAS, J.,
dissenting) (resolving the issue, nevermind that the Court
of Appeals left it unaddressed); post, at 1–2 (ALITO, J.,
dissenting) (upbraiding the Court for addressing the sole
issue decided by the Court of Appeals and characterizing
the Court’s answer as “unnecessary” because the Court,
instead, should have decided an issue the Court of Appeals
did not decide). The question whether reasonable suspi­
cion of criminal activity justified detaining Rodriguez
beyond completion of the traffic infraction investigation,
therefore, remains open for Eighth Circuit consideration
on remand.
                        *   *    *
  For the reasons stated, the judgment of the United
States Court of Appeals for the Eighth Circuit is vacated,
and the case is remanded for further proceedings con­
sistent with this opinion.
                                          It is so ordered.
                 Cite as: 575 U. S. ____ (2015)          1

                   KENNEDY, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                         No. 13–9972
                         _________________


        DENNYS RODRIGUEZ, PETITIONER v.

                UNITED STATES

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE EIGHTH CIRCUIT

                        [April 21, 2015] 


  JUSTICE KENNEDY, dissenting.
  My join in JUSTICE THOMAS’ dissenting opinion does not
extend to Part III. Although the issue discussed in that
Part was argued here, the Court of Appeals has not ad-
dressed that aspect of the case in any detail. In my view
the better course would be to allow that court to do so in
the first instance.
                 Cite as: 575 U. S. ____ (2015)           1

                    THOMAS, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                         No. 13–9972
                         _________________


        DENNYS RODRIGUEZ, PETITIONER v.

                UNITED STATES

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE EIGHTH CIRCUIT

                        [April 21, 2015] 


  JUSTICE THOMAS, with whom JUSTICE ALITO joins, and
with whom JUSTICE KENNEDY joins as to all but Part III,
dissenting.
  Ten years ago, we explained that “conducting a dog sniff
[does] not change the character of a traffic stop that is
lawful at its inception and otherwise executed in a reason-
able manner.” Illinois v. Caballes, 543 U. S. 405, 408
(2005). The only question here is whether an officer exe-
cuted a stop in a reasonable manner when he waited to
conduct a dog sniff until after he had given the driver a
written warning and a backup unit had arrived, bringing
the overall duration of the stop to 29 minutes. Because
the stop was reasonably executed, no Fourth Amendment
violation occurred. The Court’s holding to the contrary
cannot be reconciled with our decision in Caballes or a
number of common police practices. It was also unneces-
sary, as the officer possessed reasonable suspicion to
continue to hold the driver to conduct the dog sniff. I
respectfully dissent.
                             I
  The Fourth Amendment protects “[t]he right of the
people to be secure in their persons, houses, papers, and
effects, against unreasonable searches and seizures.”
U. S. Const., Amdt. 4. As the text indicates, and as we
2              RODRIGUEZ v. UNITED STATES

                     THOMAS, J., dissenting

have repeatedly confirmed, “the ultimate touchstone of the
Fourth Amendment is ‘reasonableness.’ ” Brigham City v.
Stuart, 547 U. S. 398, 403 (2006). We have defined rea-
sonableness “in objective terms by examining the totality
of the circumstances,” Ohio v. Robinette, 519 U. S. 33, 39
(1996), and by considering “the traditional protections
against unreasonable searches and seizures afforded by
the common law at the time of the framing,” Atwater v.
Lago Vista, 532 U. S. 318, 326 (2001) (internal quotation
marks omitted). When traditional protections have not
provided a definitive answer, our precedents have “ana-
lyzed a search or seizure in light of traditional standards
of reasonableness by assessing, on the one hand, the de-
gree to which it intrudes upon an individual’s privacy and,
on the other, the degree to which it is needed for the pro-
motion of legitimate governmental interests.” Virginia v.
Moore, 553 U. S. 164, 171 (2008) (internal quotation
marks omitted).
   Although a traffic stop “constitutes a ‘seizure’ of ‘per-
sons’ within the meaning of [the Fourth Amendment],”
such a seizure is constitutionally “reasonable where the
police have probable cause to believe that a traffic viola-
tion has occurred.” Whren v. United States, 517 U. S. 806,
809–810 (1996). But “a seizure that is lawful at its incep-
tion can violate the Fourth Amendment if its manner of
execution unreasonably infringes interests protected by
the Constitution.” Caballes, supra, at 407.
   Because Rodriguez does not dispute that Officer Struble
had probable cause to stop him, the only question is
whether the stop was otherwise executed in a reasonable
manner. See Brief for Appellant in No. 13–1176 (CA8),
p. 4, n. 2. I easily conclude that it was. Approximately 29
minutes passed from the time Officer Struble stopped
Rodriguez until his narcotics-detection dog alerted to the
presence of drugs. That amount of time is hardly out of
the ordinary for a traffic stop by a single officer of a vehi-
                 Cite as: 575 U. S. ____ (2015)            3

                    THOMAS, J., dissenting

cle containing multiple occupants even when no dog sniff
is involved. See, e.g., United States v. Ellis, 497 F. 3d 606
(CA6 2007) (22 minutes); United States v. Barragan, 379
F. 3d 524 (CA8 2004) (approximately 30 minutes). During
that time, Officer Struble conducted the ordinary activities
of a traffic stop—he approached the vehicle, questioned
Rodriguez about the observed violation, asked Pollman
about their travel plans, ran serial warrant checks on
Rodriguez and Pollman, and issued a written warning to
Rodriguez. And when he decided to conduct a dog sniff, he
took the precaution of calling for backup out of concern for
his safety. See 741 F. 3d 905, 907 (CA8 2014); see also
Pennsylvania v. Mimms, 434 U. S. 106, 110 (1977) (per
curiam) (officer safety is a “legitimate and weighty” con-
cern relevant to reasonableness).
   As Caballes makes clear, the fact that Officer Struble
waited until after he gave Rodriguez the warning to con-
duct the dog sniff does not alter this analysis. Because
“the use of a well-trained narcotics-detection dog . . . gen-
erally does not implicate legitimate privacy interests,” 543
U. S., at 409, “conducting a dog sniff would not change the
character of a traffic stop that is lawful at its inception
and otherwise executed in a reasonable manner,” id., at
408. The stop here was “lawful at its inception and other-
wise executed in a reasonable manner.” Ibid. As in Ca-
balles, “conducting a dog sniff [did] not change the charac-
ter of [the] traffic stop,” ibid., and thus no Fourth
Amendment violation occurred.
                             II
  Rather than adhere to the reasonableness requirement
that we have repeatedly characterized as the “touchstone
of the Fourth Amendment,” Brigham City, supra, at 403,
the majority constructed a test of its own that is incon-
sistent with our precedents.
4              RODRIGUEZ v. UNITED STATES

                     THOMAS, J., dissenting


                               A

   The majority’s rule requires a traffic stop to “en[d] when
tasks tied to the traffic infraction are—or reasonably
should have been—completed.” Ante, at 5. “If an officer
can complete traffic-based inquiries expeditiously, then
that is the amount of time reasonably required to complete
the stop’s mission” and he may hold the individual no
longer. Ante, at 8 (internal quotation marks and altera-
tions omitted). The majority’s rule thus imposes a one-
way ratchet for constitutional protection linked to the
characteristics of the individual officer conducting the
stop: If a driver is stopped by a particularly efficient of-
ficer, then he will be entitled to be released from the traf-
fic stop after a shorter period of time than a driver stopped
by a less efficient officer. Similarly, if a driver is stopped
by an officer with access to technology that can shorten a
records check, then he will be entitled to be released from
the stop after a shorter period of time than an individual
stopped by an officer without access to such technology.
   I “cannot accept that the search and seizure protections
of the Fourth Amendment are so variable and can be made
to turn upon such trivialities.” Whren, 517 U. S., at 815
(citations omitted). We have repeatedly explained that the
reasonableness inquiry must not hinge on the characteris-
tics of the individual officer conducting the seizure. We
have held, for example, that an officer’s state of mind
“does not invalidate [an] action taken as long as the cir-
cumstances, viewed objectively, justify that action.” Id., at
813 (internal quotation marks omitted). We have spurned
theories that would make the Fourth Amendment “change
with local law enforcement practices.” Moore, supra, at
172. And we have rejected a rule that would require the
offense establishing probable cause to be “closely related
to” the offense identified by the arresting officer, as such a
rule would make “the constitutionality of an arrest . . .
vary from place to place and from time to time, depending
                 Cite as: 575 U. S. ____ (2015)            5

                    THOMAS, J., dissenting

on whether the arresting officer states the reason for the
detention and, if so, whether he correctly identifies a
general class of offense for which probable cause exists.”
Devenpeck v. Alford, 543 U. S. 146, 154 (2004) (internal
quotation marks and citation omitted). In Devenpeck, a
unanimous Court explained: “An arrest made by a knowl-
edgeable, veteran officer would be valid, whereas an arrest
made by a rookie in precisely the same circumstances
would not. We see no reason to ascribe to the Fourth
Amendment such arbitrarily variable protection.” Ibid.
  The majority’s logic would produce similarly arbitrary
results. Under its reasoning, a traffic stop made by a
rookie could be executed in a reasonable manner, whereas
the same traffic stop made by a knowledgeable, veteran
officer in precisely the same circumstances might not, if in
fact his knowledge and experience made him capable of
completing the stop faster. We have long rejected inter-
pretations of the Fourth Amendment that would produce
such haphazard results, and I see no reason to depart from
our consistent practice today.
                              B
   As if that were not enough, the majority also limits the
duration of the stop to the time it takes the officer to
complete a narrow category of “traffic-based inquiries.”
Ante, at 8. According to the majority, these inquiries
include those that “serve the same objective as enforce-
ment of the traffic code: ensuring that vehicles on the road
are operated safely and responsibly.” Ante, at 6. Inquiries
directed to “detecting evidence of ordinary criminal
wrongdoing” are not traffic-related inquiries and thus
cannot count toward the overall duration of the stop. Ibid.
(internal quotation marks and alteration omitted).
   The combination of that definition of traffic-related
inquiries with the majority’s officer-specific durational
limit produces a result demonstrably at odds with our
6               RODRIGUEZ v. UNITED STATES

                     THOMAS, J., dissenting

decision in Caballes. Caballes expressly anticipated that a
traffic stop could be reasonably prolonged for officers to
engage in a dog sniff. We explained that no Fourth
Amendment violation had occurred in Caballes, where the
“duration of the stop . . . was entirely justified by the
traffic offense and the ordinary inquiries incident to such
a stop,” but suggested a different result might attend a
case “involving a dog sniff that occurred during an unrea-
sonably prolonged traffic stop.” 543 U. S., at 407–408
(emphasis added). The dividing line was whether the
overall duration of the stop exceeded “the time reasonably
required to complete th[e] mission,” id., at 407, not, as the
majority suggests, whether the duration of the stop “in
fact” exceeded the time necessary to complete the traffic-
related inquiries, ante, at 8.
   The majority’s approach draws an artificial line between
dog sniffs and other common police practices. The lower
courts have routinely confirmed that warrant checks are a
constitutionally permissible part of a traffic stop, see, e.g.,
United States v. Simmons, 172 F. 3d 775, 778 (CA11
1999); United States v. Mendez, 118 F. 3d 1426, 1429
(CA10 1997); United States v. Shabazz, 993 F. 2d 431, 437
(CA5 1993), and the majority confirms that it finds no
fault in these measures, ante, at 6. Yet its reasoning
suggests the opposite. Such warrant checks look more like
they are directed to “detecting evidence of ordinary crimi-
nal wrongdoing” than to “ensuring that vehicles on the
road are operated safely and responsibly.” Ante, at 6
(internal quotation marks and alteration omitted). Per-
haps one could argue that the existence of an outstanding
warrant might make a driver less likely to operate his
vehicle safely and responsibly on the road, but the same
could be said about a driver in possession of contraband.
A driver confronted by the police in either case might try
to flee or become violent toward the officer. But under the
majority’s analysis, a dog sniff, which is directed at uncov-
                  Cite as: 575 U. S. ____ (2015)             7

                     THOMAS, J., dissenting

ering that problem, is not treated as a traffic-based in-
quiry. Warrant checks, arguably, should fare no better.
The majority suggests that a warrant check is an ordinary
inquiry incident to a traffic stop because it can be used “ ‘to
determine whether the apparent traffic violator is wanted
for one or more previous traffic offenses.’ ” Ante, at 6
(quoting 4 W. LaFave, Search and Seizure §9.3(c), p. 516
(5th ed. 2012)). But as the very treatise on which the
majority relies notes, such checks are a “manifest[ation of]
the ‘war on drugs’ motivation so often underlying [routine
traffic] stops,” and thus are very much like the dog sniff in
this case. Id., §9.3(c), at 507–508.
   Investigative questioning rests on the same basis as the
dog sniff. “Asking questions is an essential part of police
investigations.” Hiibel v. Sixth Judicial Dist. Court of
Nev., Humboldt Cty., 542 U. S. 177, 185 (2004). And the
lower courts have routinely upheld such questioning dur-
ing routine traffic stops. See, e.g., United States v. Rivera,
570 F. 3d 1009, 1013 (CA8 2009); United States v. Childs,
277 F. 3d 947, 953–954 (CA7 2002). The majority’s rea-
soning appears to allow officers to engage in some ques-
tioning aimed at detecting evidence of ordinary criminal
wrongdoing. Ante, at 5. But it is hard to see how such
inquiries fall within the “seizure’s ‘mission’ [of ] ad-
dress[ing] the traffic violation that warranted the stop,” or
“attend[ing] to related safety concerns.” Ibid. Its reason-
ing appears to come down to the principle that dogs are
different.
                             C
   On a more fundamental level, the majority’s inquiry
elides the distinction between traffic stops based on prob-
able cause and those based on reasonable suspicion.
Probable cause is the “traditional justification” for the
seizure of a person. Whren, 517 U. S., at 817 (emphasis
deleted); see also Dunaway v. New York, 442 U. S. 200,
8               RODRIGUEZ v. UNITED STATES

                      THOMAS, J., dissenting

207–208 (1979). This Court created an exception to that
rule in Terry v. Ohio, 392 U. S. 1 (1968), permitting “police
officers who suspect criminal activity to make limited
intrusions on an individual’s personal security based on
less than probable cause,” Michigan v. Summers, 452 U. S.
692, 698 (1981). Reasonable suspicion is the justification
for such seizures. Prado Navarette v. California, 572 U. S.
___, ___ (2014) (slip op., at 3).
   Traffic stops can be initiated based on probable cause or
reasonable suspicion. Although the Court has commented
that a routine traffic stop is “more analogous to a so-called
‘Terry stop’ than to a formal arrest,” it has rejected the
notion “that a traffic stop supported by probable cause
may not exceed the bounds set by the Fourth Amendment
on the scope of a Terry stop.” Berkemer v. McCarty, 468
U. S. 420, 439, and n. 29 (1984) (citation omitted).
   Although all traffic stops must be executed reasonably,
our precedents make clear that traffic stops justified by
reasonable suspicion are subject to additional limitations
that those justified by probable cause are not. A traffic
stop based on reasonable suspicion, like all Terry stops,
must be “justified at its inception” and “reasonably related
in scope to the circumstances which justified the interfer-
ence in the first place.” Hiibel, 542 U. S., at 185 (internal
quotation marks omitted). It also “cannot continue for an
excessive period of time or resemble a traditional arrest.”
Id., at 185–186 (citation omitted). By contrast, a stop
based on probable cause affords an officer considerably
more leeway. In such seizures, an officer may engage in a
warrantless arrest of the driver, Atwater, 532 U. S., at
354, a warrantless search incident to arrest of the driver,
Riley v. California, 573 U. S. ___, ___ (2014) (slip op., at 5),
and a warrantless search incident to arrest of the vehicle
if it is reasonable to believe evidence relevant to the crime
of arrest might be found there, Arizona v. Gant, 556 U. S.
332, 335 (2009).
                  Cite as: 575 U. S. ____ (2015)             9

                     THOMAS, J., dissenting

   The majority casually tosses this distinction aside. It
asserts that the traffic stop in this case, which was undis-
putedly initiated on the basis of probable cause, can last
no longer than is in fact necessary to effectuate the mis-
sion of the stop. Ante, at 8. And, it assumes that the
mission of the stop was merely to write a traffic ticket,
rather than to consider making a custodial arrest. Ante,
at 5. In support of that durational requirement, it relies
primarily on cases involving Terry stops. See ante, at 5–7
(citing Arizona v. Johnson, 555 U. S. 323 (2009) (analyzing
“stop and frisk” of passenger in a vehicle temporarily
seized for a traffic violation); United States v. Sharpe, 470
U. S. 675 (1985) (analyzing seizure of individuals based on
suspicion of marijuana trafficking); Florida v. Royer, 460
U. S. 491 (1983) (plurality opinion) (analyzing seizure of
man walking through airport on suspicion of narcotics
activity)).
   The only case involving a traffic stop based on probable
cause that the majority cites for its rule is Caballes. But,
that decision provides no support for today’s restructuring
of our Fourth Amendment jurisprudence. In Caballes, the
Court made clear that, in the context of a traffic stop
supported by probable cause, “a dog sniff would not change
the character of a traffic stop that is lawful at its inception
and otherwise executed in a reasonable manner.” 543
U. S., at 408. To be sure, the dissent in Caballes would
have “appl[ied] Terry’s reasonable-relation test . . . to
determine whether the canine sniff impermissibly ex-
panded the scope of the initially valid seizure of Caballes.”
Id., at 420 (GINSBURG, J., dissenting). But even it conceded
that the Caballes majority had “implicitly [rejected] the
application of Terry to a traffic stop converted, by calling
in a dog, to a drug search.” Id., at 421.
   By strictly limiting the tasks that define the durational
scope of the traffic stop, the majority accomplishes today
what the Caballes dissent could not: strictly limiting the
10              RODRIGUEZ v. UNITED STATES

                      THOMAS, J., dissenting

scope of an officer’s activities during a traffic stop justified
by probable cause. In doing so, it renders the difference
between probable cause and reasonable suspicion virtually
meaningless in this context. That shift is supported nei-
ther by the Fourth Amendment nor by our precedents
interpreting it. And, it results in a constitutional frame-
work that lacks predictability. Had Officer Struble ar-
rested, handcuffed, and taken Rodriguez to the police
station for his traffic violation, he would have complied
with the Fourth Amendment. See Atwater, supra, at 354–
355. But because he made Rodriguez wait for seven or
eight extra minutes until a dog arrived, he evidently
committed a constitutional violation. Such a view of the
Fourth Amendment makes little sense.
                              III
   Today’s revision of our Fourth Amendment jurispru-
dence was also entirely unnecessary. Rodriguez suffered
no Fourth Amendment violation here for an entirely inde-
pendent reason: Officer Struble had reasonable suspicion
to continue to hold him for investigative purposes. Our
precedents make clear that the Fourth Amendment per-
mits an officer to conduct an investigative traffic stop
when that officer has “a particularized and objective basis
for suspecting the particular person stopped of criminal
activity.” Prado Navarette, 572 U. S., at ___ (slip op., at 3)
(internal quotation marks omitted). Reasonable suspicion
is determined by looking at “the whole picture,” ibid.,
taking into account “the factual and practical considera-
tions of everyday life on which reasonable and prudent
men, not legal technicians, act,” Ornelas v. United States,
517 U. S. 690, 695 (1996) (internal quotation marks
omitted).
   Officer Struble testified that he first became suspicious
that Rodriguez was engaged in criminal activity for a
number of reasons. When he approached the vehicle, he
                 Cite as: 575 U. S. ____ (2015)          11

                    THOMAS, J., dissenting

smelled an “overwhelming odor of air freshener coming
from the vehicle,” which is, in his experience, “a common
attempt to conceal an odor that [people] don’t want . . . to
be smelled by the police.” App. 20–21. He also observed,
upon approaching the front window on the passenger side
of the vehicle, that Rodriguez’s passenger, Scott Pollman,
appeared nervous. Pollman pulled his hat down low,
puffed nervously on a cigarette, and refused to make eye
contact with him. The officer thought he was “more nerv-
ous than your typical passenger” who “do[esn’t] have
anything to worry about because [t]hey didn’t commit a
[traffic] violation.” Id., at 34.
   Officer Struble’s interactions with the vehicle’s occu-
pants only increased his suspicions. When he asked Rod-
riguez why he had driven onto the shoulder, Rodriguez
claimed that he swerved to avoid a pothole. But that story
could not be squared with Officer Struble’s observation of
the vehicle slowly driving off the road before being jerked
back onto it. And when Officer Struble asked Pollman
where they were coming from and where they were going,
Pollman told him they were traveling from Omaha, Ne-
braska, back to Norfolk, Nebraska, after looking at a
vehicle they were considering purchasing. Pollman told
the officer that he had neither seen pictures of the vehicle
nor confirmed title before the trip. As Officer Struble
explained, it “seemed suspicious” to him “to drive . . .
approximately two hours . . . late at night to see a vehicle
sight unseen to possibly buy it,” id., at 26, and to go from
Norfolk to Omaha to look at it because “[u]sually people
leave Omaha to go get vehicles, not the other way around”
due to higher Omaha taxes, id., at 65.
   These facts, taken together, easily meet our standard for
reasonable suspicion. “[N]ervous, evasive behavior is a
pertinent factor in determining reasonable suspicion,”
Illinois v. Wardlow, 528 U. S. 119, 124 (2000), and both
vehicle occupants were engaged in such conduct. The
12             RODRIGUEZ v. UNITED STATES

                     THOMAS, J., dissenting

officer also recognized heavy use of air freshener, which, in
his experience, indicated the presence of contraband in the
vehicle. “[C]ommonsense judgments and inferences about
human behavior” further support the officer’s conclusion
that Pollman’s story about their trip was likely a cover
story for illegal activity. Id., at 125. Taking into account
all the relevant facts, Officer Struble possessed reasonable
suspicion of criminal activity to conduct the dog sniff.
  Rodriguez contends that reasonable suspicion cannot
exist because each of the actions giving rise to the officer’s
suspicions could be entirely innocent, but our cases easily
dispose of that argument. Acts that, by themselves, might
be innocent can, when taken together, give rise to reason-
able suspicion. United States v. Arvizu, 534 U. S. 266,
274–275 (2002). Terry is a classic example, as it involved
two individuals repeatedly walking back and forth, looking
into a store window, and conferring with one another as
well as with a third man. 392 U. S., at 6. The Court
reasoned that this “series of acts, each of them perhaps
innocent in itself, . . . together warranted further investi-
gation,” id., at 22, and it has reiterated that analysis in a
number of cases, see, e.g., Arvizu, supra, at 277; United
States v. Sokolow, 490 U. S. 1, 9–10 (1989). This one is no
different.
                        *    *     *
  I would conclude that the police did not violate the
Fourth Amendment here. Officer Struble possessed prob-
able cause to stop Rodriguez for driving on the shoulder,
and he executed the subsequent stop in a reasonable
manner. Our decision in Caballes requires no more. The
majority’s holding to the contrary is irreconcilable with
Caballes and a number of other routine police practices,
distorts the distinction between traffic stops justified by
probable cause and those justified by reasonable suspicion,
and abandons reasonableness as the touchstone of the
Fourth Amendment. I respectfully dissent.
                      Cite as: 575 U. S. ____ (2015)          1

                           ALITO, J., dissenting

SUPREME COURT OF THE UNITED STATES
                               _________________

                               No. 13–9972
                               _________________


            DENNYS RODRIGUEZ, PETITIONER v.

                    UNITED STATES

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE EIGHTH CIRCUIT

                             [April 21, 2015] 


   JUSTICE ALITO, dissenting.
   This is an unnecessary,1 impractical, and arbitrary
decision. It addresses a purely hypothetical question:
whether the traffic stop in this case would be unreason-
able if the police officer, prior to leading a drug-sniffing dog
around the exterior of petitioner’s car, did not already
have reasonable suspicion that the car contained drugs.
In fact, however, the police officer did have reasonable
suspicion, and, as a result, the officer was justified in
detaining the occupants for the short period of time (seven
or eight minutes) that is at issue.
   The relevant facts are not in dispute. Officer Struble,
who made the stop, was the only witness at the suppres-
sion hearing, and his testimony about what happened was
not challenged. Defense counsel argued that the facts
recounted by Officer Struble were insufficient to establish
reasonable suspicion, but defense counsel did not dispute
those facts or attack the officer’s credibility. Similarly, the
Magistrate Judge who conducted the hearing did not
question the officer’s credibility.          And as JUSTICE
THOMAS’s opinion shows, the facts recounted by Officer
Struble “easily meet our standard for reasonable suspi-
cion.” Ante, at 11 (dissenting opinion); see also, e.g., United
——————
 1 See   Brief in Opposition 11–14.
2              RODRIGUEZ v. UNITED STATES

                     ALITO, J., dissenting

States v. Carpenter, 462 F. 3d 981, 986–987 (CA8 2006)
(finding reasonable suspicion for a dog sniff based on
implausible travel plans and nervous conduct); United
States v. Ludwig, 641 F. 3d 1243, 1248–1250 (CA10 2011)
(finding reasonable suspicion for a dog sniff where, among
other things, the officer smelled “strong masking odors,”
the defendant’s “account of his travel was suspect,” and
the defendant “was exceptionally nervous throughout his
encounter”).
   Not only does the Court reach out to decide a question
not really presented by the facts in this case, but the
Court’s answer to that question is arbitrary. The Court
refuses to address the real Fourth Amendment question:
whether the stop was unreasonably prolonged. Instead,
the Court latches onto the fact that Officer Struble deliv-
ered the warning prior to the dog sniff and proclaims that
the authority to detain based on a traffic stop ends when a
citation or warning is handed over to the driver. The
Court thus holds that the Fourth Amendment was vio-
lated, not because of the length of the stop, but simply be-
cause of the sequence in which Officer Struble chose to
perform his tasks.
   This holding is not only arbitrary; it is perverse since
Officer Struble chose that sequence for the purpose of
protecting his own safety and possibly the safety of others.
See App. 71–72. Without prolonging the stop, Officer
Struble could have conducted the dog sniff while one of the
tasks that the Court regards as properly part of the traffic
stop was still in progress, but that sequence would have
entailed unnecessary risk. At approximately 12:19 a.m.,
after collecting Pollman’s driver’s license, Officer Struble
did two things. He called in the information needed to do
a records check on Pollman (a step that the Court recog-
nizes was properly part of the traffic stop), and he re-
quested that another officer report to the scene. Officer
Struble had decided to perform a dog sniff but did not
                  Cite as: 575 U. S. ____ (2015)            3

                      ALITO, J., dissenting

want to do that without another officer present. When
occupants of a vehicle who know that their vehicle con-
tains a large amount of illegal drugs see that a drug-
sniffing dog has alerted for the presence of drugs, they will
almost certainly realize that the police will then proceed to
search the vehicle, discover the drugs, and make arrests.
Thus, it is reasonable for an officer to believe that an alert
will increase the risk that the occupants of the vehicle will
attempt to flee or perhaps even attack the officer. See,
e.g., United States v. Dawdy, 46 F. 3d 1427, 1429 (CA8
1995) (recounting scuffle between officer and defendant
after drugs were discovered).
   In this case, Officer Struble was concerned that he was
outnumbered at the scene, and he therefore called for
backup and waited for the arrival of another officer before
conducting the sniff. As a result, the sniff was not com-
pleted until seven or eight minutes after he delivered the
warning. But Officer Struble could have proceeded with
the dog sniff while he was waiting for the results of the
records check on Pollman and before the arrival of the
second officer. The drug-sniffing dog was present in Of-
ficer Struble’s car. If he had chosen that riskier sequence
of events, the dog sniff would have been completed before
the point in time when, according to the Court’s analysis,
the authority to detain for the traffic stop ended. Thus, an
action that would have been lawful had the officer made
the unreasonable decision to risk his life became un-
lawful when the officer made the reasonable decision to wait
a few minutes for backup. Officer Struble’s error—
apparently—was following prudent procedures motivated
by legitimate safety concerns. The Court’s holding there-
fore makes no practical sense. And nothing in the Fourth
Amendment, which speaks of reasonableness, compels this
arbitrary line.
   The rule that the Court adopts will do little good going
4                 RODRIGUEZ v. UNITED STATES

                          ALITO, J., dissenting

forward.2 It is unlikely to have any appreciable effect on
the length of future traffic stops. Most officers will learn
the prescribed sequence of events even if they cannot
fathom the reason for that requirement. (I would love to
be the proverbial fly on the wall when police instructors
teach this rule to officers who make traffic stops.)
  For these reasons and those set out in JUSTICE
THOMAS’s opinion, I respectfully dissent.




——————
    2 It
       is important to note that the Court’s decision does not affect pro-
cedures routinely carried out during traffic stops, including “checking
the driver’s license, determining whether there are outstanding war-
rants against the driver, and inspecting the automobile’s registration
and proof of insurance.” Ante, at 6. And the Court reaffirms that police
“may conduct certain unrelated checks during an otherwise lawful
traffic stop.” Ibid. Thus, it remains true that police may ask questions
aimed at uncovering other criminal conduct and may order occupants
out of their car during a valid stop. See Arizona v. Johnson, 555 U. S.
323, 333 (2009); Maryland v. Wilson, 519 U. S. 408, 414–415 (1997);
Pennsylvania v. Mimms, 434 U. S. 106, 111 (1977) (per curiam).
