argued
february
decided
june
fourth
amendment
held
allow
roving
patrol
border
patrol
stop
vehicle
near
mexican
border
question
occupants
citizenship
immigration
status
ground
suspicion
occupants
appear
mexican
ancestry
except
border
functional
equivalents
patrolling
officers
may
stop
vehicles
aware
specific
articulable
facts
together
rational
inferences
therefrom
reasonably
warranting
suspicion
vehicles
contain
aliens
may
illegally
country
pp
important
governmental
interest
preventing
illegal
entry
aliens
border
minimal
intrusion
brief
stop
absence
practical
alternatives
policing
border
officer
whose
observations
lead
reasonably
suspect
particular
vehicle
may
contain
aliens
illegally
country
may
stop
car
briefly
question
driver
passengers
citizenship
immigration
status
ask
explain
suspicious
circumstances
detention
search
must
based
consent
probable
cause
pp
allow
roving
patrols
broad
unlimited
discretion
urged
government
stop
vehicles
border
area
without
reason
suspect
violated
law
reasonable
fourth
amendment
pp
assuming
congress
power
admit
aliens
condition
submit
reasonable
questioning
right
country
power
diminish
fourth
amendment
rights
citizens
may
mistaken
aliens
fourth
amendment
therefore
forbids
stopping
persons
questioning
citizenship
less
reasonable
suspicion
may
aliens
pp
powell
delivered
opinion
brennan
stewart
marshall
rehnquist
joined
rehnquist
filed
concurring
opinion
post
burger
filed
opinion
concurring
judgment
blackmun
joined
post
douglas
filed
opinion
concurring
judgment
post
white
filed
opinion
concurring
judgment
blackmun
joined
post
deputy
solicitor
general
frey
argued
cause
briefs
solicitor
general
bork
assistant
attorney
general
petersen
acting
assistant
attorney
general
keeney
mark
evans
peter
shannon
jerome
feit
john
cleary
appointment
argued
cause
respondent
brief
charles
sevilla
sanford
jay
rosen
filed
brief
mexican
american
legal
defense
educational
fund
amicus
curiae
urging
affirmance
justice
powell
delivered
opinion
case
raises
questions
border
patrol
authority
stop
automobiles
areas
near
mexican
border
differs
decision
border
patrol
claim
authority
search
cars
question
occupants
citizenship
immigration
status
part
regular
operations
southern
california
border
patrol
operates
fixed
checkpoint
interstate
highway
south
san
clemente
evening
march
checkpoint
closed
inclement
weather
two
officers
observing
northbound
traffic
patrol
car
parked
side
highway
road
dark
using
patrol
car
headlights
illuminate
passing
cars
pursued
respondent
car
stopped
saying
later
reason
three
occupants
appeared
mexican
descent
officers
questioned
respondent
two
passengers
citizenship
learned
passengers
aliens
entered
country
illegally
three
arrested
respondent
charged
two
counts
knowingly
transporting
illegal
immigrants
violation
immigration
nationality
act
stat
trial
respondent
moved
suppress
testimony
two
passengers
claiming
evidence
fruit
illegal
seizure
trial
denied
motion
aliens
testified
trial
respondent
convicted
counts
respondent
appeal
pending
appeals
ninth
circuit
announced
decision
supra
holding
fourth
amendment
prohibits
use
roving
patrols
search
vehicles
without
warrant
probable
cause
points
removed
border
functional
equivalents
appeals
sitting
en
banc
held
stop
case
closely
resembled
stop
stop
traffic
checkpoint
applied
principles
held
fourth
amendment
interpreted
forbids
stopping
vehicle
even
limited
purpose
questioning
occupants
unless
officers
founded
suspicion
occupants
aliens
illegally
country
refused
find
mexican
ancestry
alone
supported
founded
suspicion
held
respondent
motion
suppress
granted
granted
certiorari
set
case
oral
argument
ortiz
post
bowen
post
government
challenge
appeals
factual
conclusion
stop
respondent
car
stop
rather
checkpoint
stop
brief
challenge
retroactive
application
supra
brief
contend
san
clemente
checkpoint
functional
equivalent
border
issue
presented
decision
whether
roving
patrol
may
stop
vehicle
area
near
border
question
occupants
ground
suspicion
occupants
appear
mexican
ancestry
reasons
follow
affirm
decision
appeals
ii
government
claims
two
sources
statutory
authority
stopping
cars
without
warrants
border
areas
section
immigration
nationality
act
authorizes
officer
employee
immigration
naturalization
service
ins
without
warrant
interrogate
alien
person
believed
alien
right
remain
geographical
limitation
authority
government
contends
least
areas
adjacent
mexican
border
person
apparent
mexican
ancestry
alone
justifies
belief
alien
satisfies
requirement
statute
section
act
authorizes
agents
without
warrant
within
reasonable
distance
external
boundary
board
search
aliens
vessel
within
territorial
waters
railway
car
aircraft
conveyance
vehicle
iii
fourth
amendment
applies
seizures
person
including
seizures
involve
brief
detention
short
traditional
arrest
davis
mississippi
terry
ohio
henever
police
officer
accosts
individual
restrains
freedom
walk
away
seized
person
fourth
amendment
requires
seizure
reasonable
categories
police
action
subject
fourth
amendment
constraints
reasonableness
seizures
depends
balance
public
interest
individual
right
personal
security
free
arbitrary
interference
law
officers
camara
municipal
government
makes
convincing
demonstration
public
interest
demands
effective
measures
prevent
illegal
entry
aliens
mexican
border
estimates
number
illegal
immigrants
vary
widely
conservative
estimate
produced
figure
one
million
ins
suggests
may
many
million
aliens
illegally
country
whatever
number
aliens
create
significant
economic
social
problems
competing
citizens
legal
resident
aliens
jobs
generating
extra
demand
social
services
aliens
vulnerable
exploitation
complain
substandard
working
conditions
without
risking
deportation
see
generally
hearings
illegal
aliens
subcommittee
house
committee
judiciary
ser
pts
government
estimated
aliens
illegally
country
mexico
baca
supp
sd
cal
mexican
border
almost
miles
long
even
vastly
reinforced
border
patrol
find
impossible
prevent
illegal
border
crossings
many
aliens
cross
mexican
border
foot
miles
away
patrolled
areas
purchase
transportation
border
area
inland
cities
find
jobs
elude
immigration
authorities
others
gain
entry
valid
temporary
permits
violate
conditions
entry
aliens
leave
border
area
private
vehicles
often
assisted
professional
alien
smugglers
border
patrol
operations
designed
prevent
inland
movement
succeed
apprehending
illegal
entrants
smugglers
deter
movement
others
threatening
apprehension
increasing
cost
illegal
transportation
valid
public
interest
must
weigh
interference
individual
liberty
results
officer
stops
automobile
questions
occupants
intrusion
modest
government
tells
us
stop
roving
patrol
usually
consumes
minute
brief
search
vehicle
occupants
visual
inspection
limited
parts
vehicle
seen
anyone
standing
alongside
according
government
required
vehicle
occupants
response
brief
question
two
possibly
production
document
evidencing
right
ibid
limited
nature
intrusion
stops
sort
may
justified
facts
amount
probable
cause
required
arrest
terry
ohio
supra
declined
expressly
decide
whether
facts
amounting
probable
cause
justify
investigative
seizure
short
arrest
approved
limited
search
weapons
protection
officer
investigating
suspicious
behavior
persons
reasonably
believed
armed
dangerous
approved
search
facts
constitute
probable
cause
believe
suspects
guilty
crime
requiring
police
officer
able
point
specific
articulable
facts
taken
together
rational
inferences
facts
reasonably
warrant
belief
safety
others
danger
see
elaborated
terry
adams
williams
holding
policeman
justified
approaching
respondent
investigate
tip
carrying
narcotics
gun
fourth
amendment
require
policeman
lacks
precise
level
information
necessary
probable
cause
arrest
simply
shrug
shoulders
allow
crime
occur
criminal
escape
contrary
terry
recognizes
may
essence
good
police
work
adopt
intermediate
response
brief
stop
suspicious
individual
order
determine
identity
maintain
status
quo
momentarily
obtaining
information
may
reasonable
light
facts
known
officer
time
unwilling
let
border
patrol
dispense
entirely
requirement
officers
must
reasonable
suspicion
justify
stops
context
border
area
stops
reasonableness
requirement
fourth
amendment
demands
something
broad
unlimited
discretion
sought
government
roads
near
border
carry
aliens
seeking
enter
country
illegally
large
volume
legitimate
traffic
well
san
diego
metropolitan
population
million
located
border
texas
two
fairly
large
metropolitan
areas
directly
border
el
paso
population
area
combined
population
confident
substantially
traffic
cities
lawful
relatively
residents
connection
illegal
entry
transportation
aliens
approve
stops
vehicles
border
area
without
suspicion
particular
vehicle
carrying
illegal
immigrants
subject
residents
areas
potentially
unlimited
interference
use
highways
solely
discretion
border
patrol
officers
formal
limitation
discretion
appears
administrative
regulation
defining
term
reasonable
distance
mean
within
air
miles
border
cfr
thus
approved
government
position
case
border
patrol
officers
stop
motorists
random
questioning
day
night
anywhere
within
air
miles
border
city
street
busy
highway
desert
road
without
reason
suspect
violated
law
convinced
legitimate
needs
law
enforcement
require
degree
interference
lawful
traffic
discuss
part
iv
infra
nature
illegal
alien
traffic
characteristics
smuggling
operations
tend
generate
articulable
grounds
identifying
violators
consequently
requirement
reasonable
suspicion
stops
allows
government
adequate
means
guarding
public
interest
also
protects
residents
border
areas
indiscriminate
official
interference
circumstances
even
though
intrusion
incident
stop
modest
conclude
reasonable
fourth
amendment
make
stops
random
basis
government
also
contends
public
interest
enforcing
conditions
legal
alien
entry
justifies
stopping
persons
may
aliens
questioning
citizenship
immigration
status
although
may
assume
purposes
case
broad
congressional
power
immigration
see
kleindienst
mandel
authorizes
congress
admit
aliens
condition
submit
reasonable
questioning
right
remain
country
power
diminish
fourth
amendment
rights
citizens
may
mistaken
aliens
reasons
fourth
amendment
forbids
stopping
vehicles
random
inquire
carrying
aliens
illegally
country
also
forbids
stopping
detaining
persons
questioning
citizenship
less
reasonable
suspicion
may
aliens
iv
effect
decision
limit
exercise
authority
granted
except
border
functional
equivalents
officers
roving
patrol
may
stop
vehicles
aware
specific
articulable
facts
together
rational
inferences
facts
reasonably
warrant
suspicion
vehicles
contain
aliens
may
illegally
country
number
factors
may
taken
account
deciding
whether
reasonable
suspicion
stop
car
border
area
officers
may
consider
characteristics
area
encounter
vehicle
proximity
border
usual
patterns
traffic
particular
road
previous
experience
alien
traffic
relevant
see
carroll
cert
denied
also
may
consider
information
recent
illegal
border
crossings
area
driver
behavior
may
relevant
erratic
driving
obvious
attempts
evade
officers
support
reasonable
suspicion
see
duprez
aspects
vehicle
may
justify
suspicion
instance
officers
say
certain
station
wagons
large
compartments
seats
spare
tires
frequently
used
transporting
concealed
aliens
see
cert
denied
wright
vehicle
may
appear
heavily
loaded
may
extraordinary
number
passengers
officers
may
observe
persons
trying
hide
see
supra
government
also
points
trained
officers
recognize
characteristic
appearance
persons
live
mexico
relying
factors
mode
dress
haircut
reply
brief
ortiz
post
situations
officer
entitled
assess
facts
light
experience
detecting
illegal
entry
smuggling
terry
ohio
case
officers
relied
single
factor
justify
stopping
respondent
car
apparent
mexican
ancestry
occupants
conclude
furnished
reasonable
grounds
believe
three
occupants
aliens
best
officers
fleeting
glimpse
persons
moving
car
illuminated
headlights
even
saw
enough
think
occupants
mexican
descent
factor
alone
justify
neither
reasonable
belief
aliens
reasonable
belief
car
concealed
aliens
illegally
country
large
numbers
naturalized
citizens
physical
characteristics
identified
mexican
ancestry
even
border
area
relatively
small
proportion
aliens
likelihood
given
person
mexican
ancestry
alien
high
enough
make
mexican
appearance
relevant
factor
standing
alone
justify
stopping
ask
aliens
judgment
appeals
affirmed
opinion
justice
white
concurring
judgment
see
post
footnotes
may
room
question
whether
voluntary
testimony
witness
trial
opposed
government
agent
testimony
objects
seized
statements
overheard
subject
suppression
fruit
illegal
search
seizure
see
cert
dismissed
improvidently
granted
since
question
raised
petition
certiorari
address
accept
respondent
contention
even
though
mention
probable
cause
legislative
history
establishes
congress
meant
condition
immigration
officers
authority
board
search
vehicles
probable
cause
believe
contained
aliens
legislative
history
simply
support
contention
estimate
one
million
produced
commissioner
ins
immigration
nationality
subcommittee
house
judiciary
committee
hearings
illegal
aliens
subcommittee
house
committee
judiciary
ser
pt
pp
higher
estimate
appears
ins
ann
iii
estimate
tends
confirmed
consistently
high
proportion
mexican
nationals
number
deportable
aliens
arrested
year
example
deportable
aliens
arrested
mexico
see
ins
ann
figure
ins
ann
case
officers
search
respondent
car
found
incriminating
evidence
validity
search
issue
changed
border
patrol
practice
searching
cars
routine
stops
government
informs
us
roving
patrols
search
vehicles
probable
cause
believe
find
illegally
present
aliens
contraband
brief
stop
case
made
without
warrant
officers
made
effort
obtain
one
occasion
decide
whether
warrant
issued
stop
cars
designated
area
basis
conditions
area
whole
absence
reason
suspect
particular
car
carrying
aliens
see
powell
concurring
camara
municipal
decision
case
takes
account
special
function
border
patrol
importance
governmental
interests
policing
border
area
character
stops
availability
alternatives
random
stops
unsupported
reasonable
suspicion
border
patrol
agents
part
enforcing
laws
regulate
highway
use
activities
nothing
inquiry
whether
motorists
vehicles
entitled
virtue
compliance
laws
governing
highway
usage
upon
public
highways
decision
thus
imply
state
local
enforcement
agencies
without
power
conduct
limited
stops
necessary
enforce
laws
regarding
drivers
licenses
vehicle
registration
truck
weights
similar
matters
noted
reserve
question
whether
border
patrol
officers
also
may
stop
persons
reasonably
believed
aliens
reason
believe
illegally
country
see
cheung
tin
wong
ins
app
au
yi
lau
ins
app
cert
denied
facts
case
require
decision
point
courts
appeals
decisions
cited
throughout
part
merely
illustrative
citation
imply
view
merits
particular
decisions
case
must
turn
totality
particular
circumstances
government
also
argues
location
stop
considered
deciding
whether
officers
adequate
reason
stop
respondent
car
appears
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justification
trial
officers
gave
reason
stop
except
apparent
mexican
ancestry
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even
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presented
broader
justification
appeals
therefore
decline
stage
case
give
weight
location
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figures
alien
registration
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mexican
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number
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assume
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immigrants
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many
persons
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origin
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bureau
census
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may
physical
appearance
similar
persons
mexican
origin
justice
rehnquist
concurring
join
opinion
think
quite
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point
however
opinion
joined
somewhat
different
majority
comprised
terms
reasoning
concerned
type
stop
involved
case
think
travelers
entering
country
may
stopped
searched
without
probable
cause
without
founded
suspicion
national
self
protection
reasonably
requiring
one
entering
country
identify
entitled
come
belongings
effects
may
lawfully
brought
carroll
strong
case
may
made
charged
enforcement
laws
conditioning
right
vehicular
use
highway
likewise
stop
motorists
using
highways
order
determine
whether
met
qualifications
prescribed
applicable
law
use
see
cady
dombrowski
biswell
regard
similar
situations
agricultural
inspections
highway
roadblocks
apprehend
known
fugitives
way
constitutionally
suspect
reason
today
decision
justice
douglas
concurring
judgment
join
affirmance
judgment
stopping
respondent
automobile
solely
occupants
appeared
mexican
ancestry
patent
violation
fourth
amendment
agree
however
standard
adopts
measure
lawfulness
officers
action
extends
suspicion
test
terry
ohio
stop
moving
automobile
dissented
adoption
suspicion
test
terry
believing
unjustified
weakening
fourth
amendment
protection
citizens
arbitrary
interference
police
remarked
infringement
personal
liberty
seizure
person
reasonable
fourth
amendment
require
police
possess
probable
cause
seize
line
draws
meaningful
distinction
officer
mere
inkling
presence
facts
within
officer
personal
knowledge
convince
reasonable
man
person
seized
committed
committing
commit
particular
crime
police
power
exercised
without
probable
cause
arbitrary
say
police
may
accost
citizens
whim
may
detain
upon
reasonable
suspicion
say
reality
police
may
accost
detain
citizens
whim
amsterdam
perspectives
fourth
amendment
rev
sure
disclaim
approval
particular
decisions
cites
applying
suspicion
test
specifying
factors
considered
without
attempting
explain
combination
necessary
satisfy
test
may
actually
induce
police
push
language
beyond
intended
limits
advance
justification
enumerated
factors
even
probative
significance
negligible
ultimately
degree
suspicion
test
actually
restrains
police
depend
upon
henceforth
upon
says
today
brethren
mean
give
suspicion
test
new
bite
applaud
intention
view
developments
since
test
launched
terry
optimistic
first
decision
invalidate
stop
basis
suspicion
standard
fact
since
terry
granted
review
case
applying
test
adams
williams
found
standard
satisfied
tip
informant
whose
credibility
established
whose
information
shown
based
upon
personal
knowledge
future
suspicion
test
provide
meaningful
restraint
police
force
must
come
vigorous
review
applications
alone
qualifying
language
today
opinion
remain
unconvinced
suspicion
test
offers
significant
protection
comprehensive
right
personal
liberty
face
governmental
intrusion
lopez
dissenting
opinion
embodied
fourth
amendment
see
lafave
street
encounters
constitution
rev