PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,               
                 Plaintiff-Appellant,
                 v.                             No. 03-4567
DEUNTE L. HUMPHRIES,
              Defendant-Appellee.
                                        
           Appeal from the United States District Court
         for the Eastern District of Virginia, at Richmond.
                 Henry E. Hudson, District Judge.
                           (CR-03-100)

                      Argued: January 22, 2004

                       Decided: June 17, 2004

Before NIEMEYER, WILLIAMS, and GREGORY, Circuit Judges.



Reversed and remanded by published opinion. Judge Niemeyer wrote
the opinion, in which Judge Williams joined. Judge Gregory wrote an
opinion concurring in the judgment.


                            COUNSEL

ARGUED: Richard Daniel Cooke, Special Assistant United States
Attorney, Alexandria, Virginia, for Appellant. Reuben Voll Greene,
JOHNSON & WALKER, P.C., Richmond, Virginia, for Appellee.
ON BRIEF: Paul J. McNulty, United States Attorney, Michael J. Els-
ton, Assistant United States Attorney, Alexandria, Virginia, for
Appellant.
2                    UNITED STATES v. HUMPHRIES
                              OPINION

NIEMEYER, Circuit Judge:

   Deunte Humphries was arrested without a warrant in a high crime
area of Richmond, Virginia, after a Richmond police officer smelled
the odor of marijuana emanating from Humphries’ person and after
Humphries walked away from the officer, disobeying orders to stop
for questioning. At the time, the officer also had reason to suspect that
Humphries was carrying a concealed weapon.

   Concluding that the officer did not have "probable cause to arrest"
Humphries, the district court suppressed the evidence seized as the
fruit of Humphries’ arrest.

   Accepting the factual findings made by the district court, we con-
clude as a matter of law that the officer had probable cause to believe
that Humphries was committing a crime, justifying his arrest. Accord-
ingly, we reverse the district court’s suppression order and remand for
further proceedings.

                                    I

   On June 25, 2003, City of Richmond Police Officers Gary Venable
and A.D. Carr were patrolling an area of Richmond known for drug
trafficking. As the officers pulled their marked police car onto a block
with 5 to 15 persons "hanging outside" in the general area, Officer
Venable saw Deunte Humphries pat his waist area. Officer Venable,
a 16-year police veteran, interpreted the waist pat to be a "security
check"; he suspected that Humphries was instinctively confirming the
presence of his weapon by "checking to make sure it [was] there."

   After they stopped their patrol car about 20 feet from Humphries
and exited the vehicle, the officers smelled a strong odor of mari-
juana. When Officer Venable began walking toward a man standing
near Humphries, he saw Humphries "out of the corner of [his] eye
quickly turn and quickly walk away." Officer Venable then followed
Humphries, saying to him, "I need to talk to you for a minute." Hum-
phries did not answer and continued walking away at a quick pace.
                     UNITED STATES v. HUMPHRIES                       3
As Officer Venable picked up his pace and got to within 5 to 10 feet
of Humphries, he smelled "the same strong odor of marijuana . . .
coming off of [Humphries’] person" as that which he had smelled
upon exiting the patrol car. Officer Venable instructed Humphries to
stop, but Humphries continued walking away at the same quick pace.

   As Humphries turned up a sidewalk to approach a house on the
3100 block of Fifth Avenue, Officer Venable again instructed Hum-
phries to stop, but Humphries ignored the order and walked quickly
to the house and began knocking on the door. Officer Venable
stopped at the foot of the stairs to the house and noted that the smell
of marijuana remained strong and particularized to Humphries. After
Humphries knocked several times, a woman opened the door and
Humphries began to enter.

   Officer Venable then said to Humphries, "That’s it. Stop. Don’t go
in the house." Humphries ignored Officer Venable’s command and
walked into the house, glancing back at the officer. As Officer Ven-
able stepped in the doorway and saw Humphries walk toward the
kitchen, Officer Venable told Humphries he was under arrest. Officer
Venable then went into the house and grabbed Humphries as he
started to round a corner and enter the kitchen.

   As Officer Venable took Humphries outside of the house, he
smelled the odor of marijuana on Humphries’ breath. Officer Venable
patted Humphries down and recovered a 9mm semi-automatic hand-
gun from the area where the officer had earlier seen Humphries pat
his waist. After recovering the weapon, Officer Venable conducted a
full search incident to arrest, finding 26 tablets of Percocet in Humph-
ries’ jacket pocket and a small amount of crack cocaine in his pants
pocket.

   Humphries was formally charged with possession of Percocet with
intent to distribute, simple possession of Percocet, possession of crack
cocaine, and possession of a firearm in furtherance of drug traffick-
ing, in violation of 21 U.S.C. §§ 841, 844 and 18 U.S.C. § 924(c).
Before trial, he filed a motion to suppress the drug and handgun evi-
dence seized incident to his arrest, contending that the evidence was
the fruit of an arrest that violated his Fourth Amendment rights. He
argued that Officer Venable did not have probable cause to arrest him,
4                    UNITED STATES v. HUMPHRIES
nor did the officer have a "reasonable, articulable, particularized sus-
picion" of crime to stop him.

   Following a hearing on Humphries’ motion, the district court
ordered the evidence suppressed. The court concluded that although
the information known to Officer Venable "was certainly enough to
give him the particularized suspicion necessary to stop the defendant
and to question him to allay his suspicion that the defendant may be
involved in the illegal possession or, perhaps more remotely, the dis-
tribution of marijuana," Officer Venable did not have probable cause
to arrest Humphries. The court apparently understood probable cause
to mean "more likely than not, [more than] 50/50."

   The government filed this appeal, challenging the district court’s
ruling suppressing the evidence seized incident to Humphries’ arrest.

                                   II

   The government does not challenge the district court’s factual find-
ings. Rather, it argues that based on the facts actually found by the
district court, Officer Venable had probable cause to arrest Humphries
and, incident to the arrest, to search him. Accordingly, the govern-
ment asserts that the district court erred in suppressing the evidence
recovered from the search incident to the arrest. Humphries responds
simply by arguing that, as a matter of law, the evidence and infer-
ences to be drawn therefrom were insufficient to establish probable
cause for his arrest.1

   Our standard of review is familiar. While we review findings of
historical fact only for clear error, we review the determination of
probable cause de novo. Ornelas v. United States, 

, 699
(1996). In our deference to fact-finding, we also give "due weight to
inferences drawn from those facts by resident judges and local law
enforcement officers." 

does not challenge Officer Venable’s warrantless entry
into the residence to make the arrest, presumably because Humphries
lacks standing, and therefore we treat his arrest as one made in a public
place.
                     UNITED STATES v. HUMPHRIES                       5
   The legal inquiry begins with the Fourth Amendment, which pro-
vides that the people are "to be secure in their persons . . . against
unreasonable searches and seizures . . . and no Warrants shall issue,
but upon probable cause." U.S. Const. amend. IV. This limitation is
made applicable to the States through the Fourteenth Amendment.
Wolf v. Colorado, 

, 27-28 (1949). Under the Fourth
Amendment, if supported by probable cause, an officer may make a
warrantless arrest of an individual in a public place. Maryland v.
Pringle, 

, 799 (2003); United States v. Watson, 

, 424 (1976); Street v. Surdyka, 

, 371-72 (4th
Cir. 1974) (holding that a warrantless arrest may be made in a public
place even if the crime for which the arrest was made was a misde-
meanor committed outside an officer’s presence). "Probable cause"
sufficient to justify an arrest requires "facts and circumstances within
the officer’s knowledge that are sufficient to warrant a prudent per-
son, or one of reasonable caution, in believing, in the circumstances
shown, that the suspect has committed, is committing, or is about to
commit an offense." Michigan v. DeFillippo, 

, 37 (1979).

   Determining whether the officer has probable cause involves an
inquiry into the totality of the circumstances. 

. Moreover, the inquiry does not involve the application of a pre-
cise legal formula or test but the commonsense and streetwise assess-
ment of the factual circumstances:

    On many occasions, we have reiterated that the probable-
    cause standard is a practical, nontechnical conception that
    deals with the factual and practical considerations of every-
    day life on which reasonable and prudent men, not legal
    technicians, act.

(internal quotation marks and citations omitted). And as we
show deference to inferences that a resident judge draws from the fac-
tual circumstances, we show similar respect to the inferences drawn
by law enforcement officers on the scene. 

-800; 

.

  In assessing the totality of the circumstances, it is appropriate to
consider specifically: an officer’s practical experience and the infer-
ences the officer may draw from that experience, see Ornelas, 517
6                    UNITED STATES v. HUMPHRIES
U.S. at 700; or the context of a high-crime area, see Illinois v. Ward-
low, 

, 124 (2000); or an individual’s presence in a high-
crime area coupled with his "[h]eadlong flight" upon noticing police,
id.; or evasive conduct that falls short of headlong flight, United
States v. Lender, 

, 154 (4th Cir. 1993); or even "seem-
ingly innocent activity" when placed in the context of surrounding
circumstances, Porterfield v. Lott, 

, 569 (4th Cir. 1998).
At bottom, however, the probable-cause standard is "incapable of pre-
cise definition or quantification into percentages because it deals with
probabilities and depends on the totality of the circumstances."

. Stripped to its essence, the question to be
answered is whether an objectively reasonable police officer, placed
in the circumstances, had a "reasonable ground for belief of guilt" that
was "particularized with respect to the person to be searched or
seized." 

found by the district court are undisputed. The court
found that as Officers Venable and Carr exited their vehicle in a high-
crime area of Richmond, "they observed [Humphries] pat his waist
area." From 20 feet away, the officers detected the distinct odor of
marijuana, and they continued to smell the marijuana as they
approached Humphries and another man standing nearby. As the offi-
cers drew near, Humphries "turned and began to walk away," and
"Officer Venable told him to stop." Humphries did not stop but
walked away at "a quick pace." As Officer Venable followed "be-
tween 5 and 10 feet" behind Humphries, he continued to smell "the
distinct odor of marijuana." The district court found that Officer Ven-
able directed Humphries to stop "on two occasions" but Humphries
ignored the orders. When Humphries approached a residence on the
3100 block of Fifth Avenue and knocked on the door, "Officer Ven-
able stood at the foot of the stairs and still smelled . . . the odor of
marijuana around the defendant." After Humphries was admitted into
the premises by a woman, Officer Venable followed him and placed
him under arrest. The district court recognized that Officer Venable
was an experienced police officer and "what he had at that time in
front of him was the odor of marijuana emanating from the defendant
at the distance of between 5 and 10 feet."

  With these undisputed facts, the legal question is now presented
whether Officer Venable had probable cause to believe that Humph-
                      UNITED STATES v. HUMPHRIES                        7
ries "ha[d] committed, [was] committing, or [was] about to commit
an offense." 

.

    Under Virginia law, it is a crime to possess marijuana, Va. Code
Ann. § 18.2-250.1, or to possess marijuana with the intent to distrib-
ute it, 

It is also a crime to carry a concealed weapon
without a permit, 

or to possess a firearm while pos-
sessing more than one pound of marijuana with the intent to distribute
it, 

   We have repeatedly held that the odor of marijuana alone can pro-
vide probable cause to believe that marijuana is present in a particular
place. In United States v. Scheetz, 

, 184 (4th Cir. 2002),
for example, we held that the smell of marijuana emanating from a
properly stopped automobile constituted probable cause to believe
that marijuana was in the vehicle, justifying its search. Similarly, in
United States v. Cephas, 

, 495 (4th Cir. 2001), we recog-
nized that the strong smell of marijuana emanating from an open
apartment door "almost certainly" provided the officer with probable
cause to believe that marijuana was present in the apartment. See also
United States v. Sifuentes, 

, 848 (4th Cir. 1974) (holding
that officers’ sight of boxes inside a van coupled with the strong odor
of marijuana permitted seizure of the boxes because they were in
"plain view, that is, obvious to the senses"). While smelling marijuana
does not assure that marijuana is still present, the odor certainly pro-
vides probable cause to believe that it is. Thus, when marijuana is
believed to be present in an automobile based on the odor emanating
therefrom, we have found probable cause to search the automobile,
and when the odor of marijuana emanates from an apartment, we have
found that there is "almost certainly" probable cause to search the
apartment. A separate question, of course, remains in these circum-
stances — whether an exception to the warrant requirement applies,
such as the automobile exception in Scheetz or the exigent circum-
stances in Cephas.

    Humphries contends that these cases are inapposite because the
present case raises the issue of probable cause to arrest, not to search.
It is true that the inquiries about whether the facts justify a search are
different from whether they justify a seizure. In the search context,
the question is whether the totality of circumstances is sufficient to
8                    UNITED STATES v. HUMPHRIES
warrant a reasonable person to believe that contraband or evidence of
a crime will be found in a particular place. 

;
Illinois v. Gates, 

, 238 (1983). Whereas in the arrest con-
text, the question is whether the totality of the circumstances indicate
to a reasonable person that a "suspect has committed, is committing,
or is about to commit" a crime. 

. But in
both cases, the quantum of facts required for the officer to search or
to seize is "probable cause," and the quantum of evidence needed to
constitute probable cause for a search or a seizure is the same. 2
Wayne R. LaFave, Search & Seizure § 3.1(b) (3d ed. 1996); compare

(arrest context), with 

(search context).

   While the odor of marijuana provides probable cause to believe
that marijuana is present, the presence of marijuana does not of itself
authorize the police either to search any place or to arrest any person
in the vicinity. Additional factors must be present to localize the pres-
ence of marijuana such that its placement will justify either the search
or the arrest. In the case of a search, when the odor emanates from
a confined location such as an automobile or an apartment, we have
held that officers may draw the conclusion that marijuana is present
in the automobile or the apartment. See 

;

. But probable cause to believe that marijuana
is located in an automobile or an apartment may not automatically
constitute probable cause to arrest all persons in the automobile or
apartment; some additional factors would generally have to be pres-
ent, indicating to the officer that those persons possessed the contra-
band. See 

-01 (holding that the presence of
cocaine and a roll of money in the passenger area of an automobile
gave officers probable cause to believe that the automobile’s occu-
pants jointly committed the crime of possession of cocaine). Thus, if
an officer smells the odor of marijuana in circumstances where the
officer can localize its source to a person, the officer has probable
cause to believe that the person has committed or is committing the
crime of possession of marijuana.

   In this case, Officers Venable and Carr smelled a strong odor of
marijuana immediately upon exiting their patrol car about 20 feet
from Humphries. Humphries was not alone on the street, however, so
the odor could not initially be tied to Humphries alone. But when
                     UNITED STATES v. HUMPHRIES                       9
Officer Venable followed Humphries as Humphries quickly walked
away, getting to within 5 to 10 feet of Humphries, he continued to
smell "the same strong odor of marijuana . . . coming off his person."
Officer Venable also smelled the odor of marijuana coming off Hum-
phries as he knocked on the door of the residence that he entered to
evade the officer.

   The district court credited Officer Venable’s testimony, and his tes-
timony that the odor of marijuana followed Humphries down the
street was sufficient to particularize the source of the odor to Humph-
ries’ person. Just as in 

, where the smell of
marijuana emanating from an automobile constituted probable cause
to believe marijuana was present in the vehicle, the odor of marijuana
emanating from Humphries was sufficient to provide Officer Venable
with probable cause to believe that marijuana was present on Humph-
ries’ person. And because Officer Venable had probable cause to
believe Humphries was presently possessing marijuana, he had proba-
ble cause to arrest him for the crime of possession.

   Other factors strengthen the conclusion that Officer Venable had
probable cause to arrest Humphries. Officer Venable’s probable-cause
calculation properly considered Humphries’ evasive conduct, even if
it fell short of "headlong flight." See 

. Hum-
phries immediately walked away as the officers approached, and
although he did not run, he walked away at a quick pace, ignoring the
officer’s commands to stop. He also ignored the officer’s command
to stop before he entered a residence. Such evasive conduct would
suggest culpability to a reasonable officer.

   In addition, as the police officers approached in their marked patrol
car, Humphries patted his waist, which Officer Venable interpreted as
a "security check," an instinctive check by Humphries to see that his
weapon was in place. Also, the entire encounter with Humphries took
place in an area known for drug trafficking. As an experienced police
officer, Officer Venable properly considered these circumstances in
his probable-cause calculation, because the increased possibility that
Humphries was carrying a weapon and was in an area known for drug
trafficking increased the possibility that Humphries was possessing
marijuana or other contraband. See 

("[A]
police officer may draw inferences based on his own experience in
10                   UNITED STATES v. HUMPHRIES
deciding whether probable cause exists"); see also Porterfield v. Lott,

, 569 (4th Cir. 1998) ("[W]hen it is considered in the
light of all of the surrounding circumstances, even ‘seemingly inno-
cent activity’ may provide a basis for finding probable cause").

   While the district court concluded that the circumstances that con-
fronted Officer Venable provided the basis for a Terry stop, see Terry
v. Ohio, 

(1968), the court rejected the claim that the cir-
cumstances provided probable cause because, as the court stated,
"probable cause means more likely than not, [more than] 50/50." If
the court rested its ultimate conclusion to suppress the evidence on
that understanding, it erred. The Supreme Court has repeatedly
admonished that the standard for probable cause is not "finely tuned"
or capable of "precise definition or quantification into percentages."

. Indeed, the Court has explicitly admon-
ished that the preponderance of the evidence standard, understood by
the district court in this case to apply, is inappropriate:

     Finely tuned standards such as proof beyond a reasonable
     doubt or by a preponderance of the evidence, useful in for-
     mal trials, have no place in the [probable-cause] decision.

, quoted in 

. Simi-
larly, we have stated that the probable-cause standard does not require
that the officer’s belief be more likely true than false. United States
v. Jones, 

, 1313 (4th Cir. 1994).

   Because Officer Venable had probable cause to believe that Hum-
phries was in possession of marijuana, he had authority to arrest him
without a warrant in a public place. See 

;

. Accordingly, we reverse the district
court’s order suppressing the evidence seized incident to Humphries’
arrest and remand for further proceedings.

                                      REVERSED AND REMANDED

GREGORY, Circuit Judge, concurring in the judgment:

   I concur only in the judgment reached by the majority. Because the
district court correctly found that Officer Venable had reasonable sus-
                      UNITED STATES v. HUMPHRIES                         11
picion to stop Humphries, detain him, and to even pat him down, the
arrest, whether valid or not, was harmless insofar as nothing addi-
tional was gained thereby. Accordingly, we need not reach the hold-
ing in the majority’s opinion.

                                     I

   Because the facts as stated in the majority’s opinion are sufficient,
I will move directly to the ultimate findings of fact made by the dis-
trict court. After hearing the arguments of counsel and taking a short
recess, the district court made brief oral findings and ruled from the
bench. The court acknowledged that Officer Venable was "an experi-
enced police officer who has testified many times in front of this
Court." J.A. at 95. The court also noted that Officer Venable smelled
marijuana "emanating from the defendant at the distance of between
5 and 10 feet." 

court was dissatisfied with the sole
"theory" offered during the suppression hearing by the Government
to support the arrest, 

seemingly proceeded
directly to formal arrest, and because the Government was "steadfast
that there was probable cause to place the defendant under arrest," the
district court understandably granted the motion to suppress. J.A. at
96. In doing so, the court concluded that Officer Venable did not have
probable cause to arrest Humphries. To the contrary, however, the
Court found that "there was an abundance of information to allow
Officer Venable to conduct an investigative detention, to question this
defendant, and to perhaps pat him down for his safety." 

review determinations of probable cause and reasonable suspi-
cion de novo. United States v. Harris, 

, 1269 (4th Cir.
1994). A reviewing court, however, should take care to (1) review
findings of historical fact only for clear error, and (2) to give due
weight to inferences drawn from those facts by resident judges. Orle-
ans v. United States, 

, 699 (1996). This is true because
"a trial judge views the facts of a particular case in light of the distinc-
tive features and events of the community. Such background facts
provide a context for the historical facts, and when seen together yield
inferences that deserve deference." 

STATES v. HUMPHRIES
   The district court clearly found that Officer Venable had the requi-
site reasonable suspicion to stop and detain Humphries. In fact, the
district court found that "there was an abundance of information to
allow Officer Venable to conduct an investigative detention, to ques-
tion this defendant, and to perhaps pat him down for his safety."1
Because the district court correctly found that Officer Venable was
justified in stopping—or attempting to stop, as it were—Humphries
and detaining him, and that he could have patted him down, United
States v. Hamlin, 

, 671-72 (4th Cir. 2003), the fact that
Officer Venable "arrested" him first and then patted him down was,
at bottom, harmless. Even if the arrest were illegal, nothing was
gained from the arrest other than that which could have been properly
seized pursuant to the lawful pat-down and investigative detention.
Surely, evidence later seized, which could have been lawfully seized
earlier, is not fruit of a poisonous tree when the "tree" itself—the stop
and pat-down—was never poisonous in the first instance.

   When suppressing evidence as the fruit of an illegal arrest, the
guiding question is "whether, granting establishment of the primary
illegality, the evidence to which instant objection is made has been
come at by exploitation of that illegality or instead by means suffi-
ciently distinguishable to be purged of the primary taint." Wong Sun
v. United States, 

, 488 (1963) (citation omitted) (empha-
  1
   The district court disagreed with the Government’s theory that Officer
Venable had probable cause to arrest Humphries for possession of mari-
juana. I note, however, that in the Government’s brief it also argued in
opposition to the motion to suppress that the "arrest" of Humphries was
an "investigative detention." Indeed, the Government’s brief before the
district court raised several theories to justify the arrest and pat-down,
including: probable cause that "criminal activity was afoot," J.A. at 23;
hot pursuit, id.; investigatory detention under Terry v. Ohio, 

(1968), 

and search incident to lawful arrest, 

Although
the Government’s arguments certainly could have been more precise, the
district court was therefore not confined to one theory of arrest, i.e., for
a misdemeanor possession offense. Perhaps the district court may have
better understood the Government’s arguments had the Government
argued specifically the theories asserted in their written briefs, instead of
devoting considerable oral argument to the holding of United States v.
Jones, 

(4th Cir. 2000), which is distinguishable from this
case.
                      UNITED STATES v. HUMPHRIES                       13
sis added). In this case, there was no "primary illegality." And, it was
the pat-down that lead Officer Venable to the weapon and contraband;
there was no other intervening police action. Moreover, the purpose
of suppressing evidence is to prevent similar misconduct on the part
of the police in the future and to deny them any benefit from such
conduct. Although one might envision a different—perhaps even
better—course of action on the part of Officer Venable, it was hardly
misconduct. Officer Venable did not embark on a fishing expedition
merely hoping that "something might turn up." Brown v. Illinois, 

, 605 (1975).2 Unlike the police misconduct in 

,
Humphries’ arrest was not effected for the purpose of obtaining evi-
dence.

  Accordingly, I would reverse the suppression order on the narrower
ground of harmless arrest.
  2
   In Brown, the Supreme Court reversed the Illinois Supreme Court’s
per se rule that a confession that is otherwise improper under the Fifth
Amendment, may not be suppressed under the Fourth Amendment. 

. The Court emphasized the prophylactic purposes of the Fourth
Amendment and held that a voluntary confession under the Fifth Amend-
ment may be suppressed under the Fourth Amendment, as fruit of a poi-
sonous tree, due to police misconduct, i.e., where "the detectives
embarked upon this expedition for evidence in the hope that something
might turn up [or where the manner an] arrest was affected gives the
appearance of having been calculated to cause surprise, fright, and confu-
sion."