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SUPREME COURT OF THE UNITED STATES
ARIZONA, et al., PETITIONERS v.
on writ of certiorari to the united states
court of appeals for the ninth circuit
[June 25, 2012]
Justice Kennedy delivered the opinion of the
To address pressing issues related to the large
number of aliens within its borders who do not have a lawful right
to be in this country, the State of Arizona in 2010 enacted a
statute called the Support Our Law Enforcement and Safe
Neighborhoods Act. The law is often referred to as S. B. 1070,
the version introduced in the state senate. See also H. 2162 (2010)
(amending S. 1070). Its stated purpose is to “discourage and
deter the unlawful entry and presence of aliens and economic
activity by persons unlawfully present in the United States.”
Note following Ariz. Rev. Stat. Ann. §11–1051 (West
2012). The law’s provisions establish an official state
policy of “attrition through enforcement.” Ibid.
The question before the Court is whether federal law preempts and
renders invalid four separate provisions of the state law.
The United States filed this suit against
Arizona, seeking to enjoin S. B. 1070 as preempted. Four provisions
of the law are at issue here. Two create new state offenses.
Section 3 makes failure to comply with federal alien-registration
requirements a state misdemeanor. Ariz. Rev. Stat. Ann.
§13–1509 (West Supp. 2011). Section 5, in relevant part,
makes it a misdemeanor for an unauthorized alien to seek or engage
in work in the State; this provision is referred to as §5(C).
See §13–2928(C). Two other provisions give specific
arrest authority and inves- tigative duties with respect to certain
aliens to state and local law enforcement officers. Section 6
authorizes officers to arrest without a warrant a person “the
officer has probable cause to believe . . . has committed
any public offense that makes the person removable from the United
States.” §13–3883(A)(5). Section 2(B) provides
that officers who conduct a stop, detention, or arrest must in some
circumstances make efforts to verify the person’s immi-
gration status with the Federal Government. See
§11–1051(B) (West 2012).
The United States District Court for the
District of Arizona issued a preliminary injunction preventing the
four provisions at issue from taking effect. 703 F. Supp. 2d 980,
1008 (2010). The Court of Appeals for the Ninth Circuit affirmed.
641 F.3d 339, 366 (2011). It agreed that the United States had
established a likelihood of success on its preemption claims. The
Court of Appeals was unanimous in its conclusion that §§3
and 5(C) were likely preempted. Judge Bea dissented from the
decision to uphold the preliminary injunction against
§§2(B) and 6. This Court granted certiorari to resolve
important questions concerning the interaction of state and federal
power with respect to the law of immigration and alien status. 565
U. S. ___ (2011).
The Government of the United States has broad,
undoubted power over the subject of immigration and the status of
aliens. See Toll
, 458 U.S.
, 10 (1982); see generally S. Legomsky & C.
Rodríguez, Immigration and Refugee Law and Policy
115–132 (5th ed. 2009). This authority rests, in part, on the
National Government’s constitutional power to
“establish an uniform Rule of Nat- uralization,”
U. S. Const., Art. I, §8, cl. 4, and its inher-
ent power as sovereign to control and conduct relations with
foreign nations, see Toll
at 10 (citing
v. Curtiss-Wright Export Corp.
, 318 (1936)).
The federal power to determine immigration
policy is well settled. Immigration policy can affect trade,
investment, tourism, and diplomatic relations for the entire
Nation, as well as the perceptions and expectations of aliens in
this country who seek the full protection of its laws. See,
Brief for Argentina et al. as Amici
see also Harisiades
, 588–589 (1952). Perceived mistreatment of aliens in
the United States may lead to harmful reciprocal treatment of
American citizens abroad. See Brief for Madeleine K. Albright
et al. as Amici Curiae
It is fundamental that foreign countries
concerned about the status, safety, and security of their nationals
in the United States must be able to confer and communicate on this
subject with one national sovereign, not the 50 separate States.
See Chy Lung
, 92 U.S.
, 279–280 (1876); see also The Federalist No. 3,
p. 39 (C. Rossiter ed. 2003) (J. Jay) (observing that federal
power would be necessary in part because “bordering States
. . . under the impulse of sudden irritation, and a quick
sense of apparent interest or injury” might take action that
would undermine foreign relations). This Court has reaffirmed that
“[o]ne of the most important and delicate of all
international relationships . . . has to do with the
protection of the just rights of a country’s own nationals
when those nationals are in another country.” Hines
, 312 U.S.
, 64 (1941).
Federal governance of immigration and alien
status is extensive and complex. Congress has specified catego-
ries of aliens who may not be admitted to the United States. See 8
U. S. C. §1182. Unlawful entry and unlawful reentry
into the country are federal offenses. §§1325, 1326. Once
here, aliens are required to register with the Federal Government
and to carry proof of status on their person. See
§§1301–1306. Failure to do so is a federal
misdemeanor. §§1304(e), 1306(a). Federal law also
authorizes States to deny noncitizens a range of public benefits,
§1622; and it imposes sanctions on employers who hire
unauthorized workers, §1324a.
Congress has specified which aliens may be
removed from the United States and the procedures for doing so.
Aliens may be removed if they were inadmissible at the time of
entry, have been convicted of certain crimes, or meet other
criteria set by federal law. See §1227. Re- moval is a civil,
not criminal, matter. A principal feature of the removal system is
the broad discretion exercised by immigration officials. See Brief
for Former Commissioners of the United States Immigration and
Naturalization Service as Amici Curiae
(hereinafter Brief for Former INS Commissioners). Federal
officials, as an initial matter, must decide whether it makes sense
to pursue removal at all. If removal proceedings commence, aliens
may seek asylum and other discretionary relief allowing them to
remain in the country or at least to leave without formal removal.
See §1229a(c)(4); see also, e.g.,
(asylum), 1229b (cancellation of removal), 1229c (voluntary
Discretion in the enforcement of immigration law
embraces immediate human concerns. Unauthorized workers trying to
support their families, for example, likely pose less danger than
alien smugglers or aliens who commit a serious crime. The equities
of an individual case may turn on many factors, including whether
the alien has children born in the United States, long ties to the
community, or a record of distinguished military service. Some
discretionary decisions involve policy choices that bear on this
Nation’s international relations. Returning an alien to his
own country may be deemed inappropriate even where he has committed
a removable offense or fails to meet the criteria for admission.
The foreign state may be mired in civil war, complicit in political
persecution, or enduring conditions that create a real risk that
the alien or his family will be harmed upon return. The dynamic
nature of relations with other countries requires the Executive
Branch to ensure that enforcement policies are con- sistent with
this Nation’s foreign policy with respect to these and other
Agencies in the Department of Homeland Security
play a major role in enforcing the country’s immigration
laws. United States Customs and Border Protection (CBP) is re-
sponsible for determining the admissibility of aliens and securing
the country’s borders. See Dept. of Homeland Security, Office
of Immigration Statistics, Immigration Enforcement Actions: 2010,
p. 1 (2011). In 2010, CBP’s Border Patrol apprehended
almost half a million people. Id.
, at 3. Immigration and
Customs Enforcement (ICE), a second agency, “conducts
criminal investigations involving the enforcement of
immigration-related statutes.” Id.
, at 2. ICE also
operates the Law Enforcement Support Center. LESC, as the Center is
known, provides immigra- tion status information to federal, state,
and local officials around the clock. See App. 91. ICE officers are
respon- sible “for the identification, apprehension, and
removal of illegal aliens from the United States.”
Immigration Enforcement Actions, supra,
at 2. Hundreds of
thousands of aliens are removed by the Federal Government every
year. See id.,
at 4 (reporting there were 387,242 removals,
and 476,405 returns without a removal order, in 2010).
The pervasiveness of federal regulation does
not di- minish the importance of immigration policy to the States.
Arizona bears many of the consequences of unlawful immigration.
Hundreds of thousands of deportable aliens are apprehended in
Arizona each year. Dept. of Homeland Security, Office of
Immigration Statistics, 2010 Yearbook of Immigration Statistics 93
(2011) (Table 35). Unauthorized aliens who remain in the State
comprise, by one es- timate, almost six percent of the population.
See Passel & Cohn, Pew Hispanic Center, U. S. Unauthorized
Im- migration Flows Are Down Sharply Since Mid-Decade 3 (2010). And
in the State’s most populous county, these aliens are
reported to be responsible for a disproportionate share of serious
crime. See, e.g.,
Camarota & Vaughan, Center for
Immigration Studies, Immigration and Crime: Assessing a Conflicted
Situation 16 (2009) (Table 3) (estimating that unauthorized aliens
comprise 8.9% of the population and are responsible for 21.8% of
the felonies in Maricopa County, which includes Phoenix).
Statistics alone do not capture the full extent
of Arizona’s concerns. Accounts in the record suggest there
is an “epidemic of crime, safety risks, serious property
damage, and environmental problems” associated with the
influx of illegal migration across private land near the Mexican
border. Brief for Petitioners 6. Phoenix is a major city of the
United States, yet signs along an interstate highway 30 miles to
the south warn the public to stay away. One reads,
“DANGER—PUBLIC WARNING—TRAVEL NOT RECOMMENDED /
Active Drug and Human Smuggling Area / Visitors May Encounter Armed
Criminals and Smuggling Vehicles Traveling at High Rates of
Speed.” App. 170; see also Brief for Petitioners 5–6.
The problems posed to the State by illegal immigration must not be
These concerns are the background for the formal
legal analysis that follows. The issue is whether, under pre-
emption principles, federal law permits Arizona to implement the
state-law provisions in dispute.
Federalism, central to the constitutional
design, adopts the principle that both the National and State
Governments have elements of sovereignty the other is bound to
respect. See Gregory
, 501 U.S.
, 457 (1991); U. S. Term Limits, Inc.
, 514 U.S.
, 838 (1995) (Kennedy, J., concurring). From the existence
of two sovereigns follows the possibility that laws can be in
conflict or at cross-purposes. The Supremacy Clause provides a
clear rule that federal law “shall be the supreme Law of the
Land; and the Judges in every State shall be bound thereby, any
Thing in the Constitution or Laws of any State to the Contrary
notwithstanding.” Art. VI, cl. 2. Under this
principle, Congress has the power to preempt state law. See
v. National Foreign Trade Council
, 530 U.S.
, 372 (2000); Gibbons
, 9 Wheat. 1,
210–211 (1824). There is no doubt that Congress may withdraw
specified powers from the States by enacting a statute containing
an express preemption provision. See, e.g., Chamber of
Commerce of United States of America
U. S. ___, ___ (2011) (slip op., at 4).
State law must also give way to federal law in
at least two other circumstances. First, the States are precluded
from regulating conduct in a field that Congress, acting within its
proper authority, has determined must be regulated by its exclusive
governance. See Gade
v. National Solid Wastes Management
Assn., 505 U.S.
, 115 (1992). The intent to displace state law altogether can
be inferred from a framework of regulation “so pervasive
. . . that Congress left no room for the States to
supplement it” or where there is a “federal interest
. . . so dominant that the federal system will be assumed
to preclude enforcement of state laws on the same subject.”
v. Santa Fe Elevator Corp.
, 331 U.S.
, 230 (1947); see English
v. General Elec.
, 496 U.S.
, 79 (1990).
Second, state laws are preempted when they
conflict with federal law. Crosby, supra,
at 372. This
includes cases where “compliance with both federal and state
regulations is a physical impossibility,” Florida Lime
& Avocado Growers, Inc.
, 373 U.S.
, 142–143 (1963), and those instances where the
challenged state law “stands as an obstacle to the
accomplishment and execution of the full purposes and objectives of
, 312 U. S., at 67; see also
, at 373 (“What is a sufficient
obstacle is a matter of judgment, to be informed by examining the
federal statute as a whole and identifying its purpose and intended
effects”). In preemption analysis, courts should assume that
“the historic police powers of the States” are not
superseded “unless that was the clear and manifest purpose of
at 230; see
, 555 U.S.
, 565 (2009).
The four challenged provisions of the state law
each must be examined under these preemption principles.
Section 3 of S. B. 1070 creates a new state
misde- meanor. It forbids the “willful failure to complete or
carry an alien registration document . . . in violation
of 8 United States Code section 1304(e) or 1306(a).” Ariz.
Rev. Stat. Ann. §11–1509(A) (West Supp. 2011). In
effect, §3 adds a state-law penalty for conduct proscribed by
federal law. The United States contends that this state enforcement
mechanism intrudes on the field of alien registration, a field in
which Congress has left no room for States to regulate. See Brief
for United States 27, 31.
The Court discussed federal alien-registration
requirements in Hines
, 312 U.S.
. In 1940, as international conflict spread, Congress added
to federal immigration law a “complete system for alien
, at 70. The new federal law struck
a careful balance. It punished an alien’s willful failure to
register but did not require aliens to carry identification cards.
There were also limits on the sharing of registration records and
fingerprints. The Court found that Congress intended the federal
plan for registration to be a “single integrated and
all-embracing system.” Id.
, at 74. Because this
“complete scheme . . . for the registration of
aliens” touched on foreign relations, it did not allow the
States to “curtail or complement” federal law or to
“enforce additional or auxiliary regulations.”
, at 66–67. As a con- sequence, the Court ruled
that Pennsylvania could not enforce its own alien-registration
program. See id.
, at 59, 74.
The present regime of federal regulation is not
identi- cal to the statutory framework considered in Hines
but it remains comprehensive. Federal law now includes a
requirement that aliens carry proof of registration. 8
U. S. C. §1304(e). Other aspects, however, have
stayed the same. Aliens who remain in the country for more than 30
days must apply for registration and be fingerprinted. Compare
§1302(a) with id.
, §452(a) (1940 ed.). Detailed
information is required, and any change of address has to be
reported to the Federal Government. Compare §§1304(a),
1305(a) (2006 ed.), with id.
, §§455(a), 456 (1940
ed.). The statute continues to provide penalties for the willful
failure to register. Compare §1306(a) (2006 ed.), with
, §457 (1940 ed.).
The framework enacted by Congress leads to the
conclusion here, as it did in Hines
, that the Federal
Government has occupied the field of alien registration. See
American Ins. Assn.
, 539 U.S.
, 419, n. 11 (2003) (characterizing Hines
field preemption case); Pennsylvania
, 504 (1956) (same); see also Dinh, Reassessing the Law of
Preemption, 88 Geo. L. J. 2085, 2098–2099, 2107 (2000)
(same). The federal statu- tory directives provide a full set of
standards governing alien registration, including the punishment
for noncompliance. It was designed as a
“ ‘harmonious whole.’ ”
at 72. Where Congress occupies an
entire field, as it has in the field of alien registration, even
complementary state regulation is impermissible. Field pre- emption
reflects a congressional decision to foreclose any state regulation
in the area, even if it is parallel to fed- eral standards. See
v. Kerr-McGee Corp.
, 249 (1984).
Federal law makes a single sovereign responsible
for maintaining a comprehensive and unified system to keep track of
aliens within the Nation’s borders. If §3 of the Arizona
statute were valid, every State could give itself independent
authority to prosecute federal registration violations,
“diminish[ing] the [Federal Government]’s control over
enforcement” and “detract[ing] from the
‘integrated scheme of regulation’ created by
Congress.” Wisconsin Dept. of Industry
, 475 U.S.
, 288–289 (1986). Even if a State may make violation
of federal law a crime in some instances, it cannot do so in a
field (like the field of alien registration) that has been occupied
by federal law. See California
, 336 U.S.
, 730–731, 733 (1949); see also In re Loney
, 375–376 (1890) (States may not impose their own
punishment for perjury in federal courts).
Arizona contends that §3 can survive
preemption because the provision has the same aim as federal law
and adopts its substantive standards. This argument not only
ignores the basic premise of field preemption—that States may
not enter, in any respect, an area the Federal Government has
reserved for itself—but also is unpersuasive on its own
terms. Permitting the State to impose its own penalties for the
federal offenses here would conflict with the careful framework
Congress adopted. Cf. Buckman Co.
, 531 U.S.
, 347–348 (2001) (States may not impose their own
punishment for fraud on the Food and Drug Administration);
Wisconsin Dept., supra,
at 288 (States may not impose their
own punishment for repeat violations of the National Labor
Relations Act). Were §3 to come into force, the State would
have the power to bring criminal charges against individuals for
violating a federal law even in circumstances where federal
officials in charge of the comprehensive scheme determine that
prosecution would frustrate federal policies.
There is a further intrusion upon the federal
scheme. Even where federal authorities believe prosecution is ap-
propriate, there is an inconsistency between §3 and fed- eral
law with respect to penalties. Under federal law, the failure to
carry registration papers is a misdemeanor that may be punished by
a fine, imprisonment, or a term of probation. See 8
U. S. C. §1304(e) (2006 ed.); 18 U. S. C.
§3561. State law, by contrast, rules out probation as a
possible sentence (and also eliminates the possibility of a
pardon). See Ariz. Rev. Stat. Ann. §13–1509(D) (West
Supp. 2011). This state framework of sanctions creates a conflict
with the plan Congress put in place. See Wisconsin Dept.
at 286 (“[C]onflict is imminent whenever two
separate remedies are brought to bear on the same activity”
(internal quotation marks omitted)).
These specific conflicts between state and
federal law simply underscore the reason for field preemption. As
it did in Hines
, the Court now concludes that, with respect
to the subject of alien registration, Congress intended to preclude
States from “complement[ing] the federal law, or enforc[ing]
additional or auxiliary regulations.” 312 U. S., at
66–67. Section 3 is preempted by federal law.
Unlike §3, which replicates federal
statutory requirements, §5(C) enacts a state criminal
prohibition where no federal counterpart exists. The provision
makes it a state misdemeanor for “an unauthorized alien to
knowingly ap- ply for work, solicit work in a public place or
perform work as an employee or independent contractor” in
Ari- zona. Ariz. Rev. Stat. Ann. §13–2928(C) (West Supp.
2011). Violations can be punished by a $2,500 fine and
incarceration for up to six months. See §13–2928(F); see
also §§13–707(A)(1) (West 2010); 13–802(A);
13–902(A)(5). The United States contends that the provision
upsets the bal- ance struck by the Immigration Reform and Control
Act of 1986 (IRCA) and must be preempted as an obstacle to the
federal plan of regulation and control.
When there was no comprehensive federal program
regulating the employment of unauthorized aliens, this Court found
that a State had authority to pass its own laws on the subject. In
1971, for example, California passed a law imposing civil penalties
on the employment of aliens who were “not entitled to lawful
residence in the United States if such employment would have an
adverse effect on lawful resident workers.” 1971 Cal. Stats.
ch. 1442, §1(a). The law was upheld against a preemption
challenge in De Canas
, 424 U.S.
(1976). De Canas
recognized that “States
possess broad authority under their police powers to regulate the
employment relationship to protect workers within the State.”
at 356. At that point, however, the Federal Government
had expressed no more than “a peripheral concern with [the]
employment of illegal entrants.” Id.
, at 360; see
, 563 U. S., at ___ (slip op., at 3).
Current federal law is substantially different
from the regime that prevailed when De Canas
Congress enacted IRCA as a comprehensive framework for
“combating the employment of illegal aliens.”
Hoffman Plastic Compounds, Inc.
, 535 U.S.
, 147 (2002). The law makes it illegal for employers to
know- ingly hire, recruit, refer, or continue to employ
unauthorized workers. See 8 U. S. C.
§§1324a(a)(1)(A), (a)(2). It also requires every employer
to verify the employment authorization status of prospective
employees. See §§1324a(a) (1)(B), (b); 8 CFR
§274a.2(b) (2012). These requirements are enforced through
criminal penalties and an escalat- ing series of civil penalties
tied to the number of times an employer has violated the
provisions. See 8 U. S. C. §§1324a(e)(4), (f);
8 CFR §274 A. 10.
This comprehensive framework does not impose
federal criminal sanctions on the employee side (i.e.,
penalties on aliens who seek or engage in unauthorized work). Under
federal law some civil penalties are imposed instead. With certain
exceptions, aliens who accept unlawful employment are not eligible
to have their status adjusted to that of a lawful permanent
resident. See 8 U. S. C. §§1255(c)(2), (c)(8).
Aliens also may be removed from the country for having engaged in
unauthorized work. See §1227(a)(1)(C)(i); 8 CFR
§214.1(e). In addition to specifying these civil consequences,
federal law makes it a crime for unauthorized workers to obtain
employment through fraudulent means. See 18 U. S. C.
§1546(b). Congress has made clear, however, that any
information employees submit to indicate their work status
“may not be used” for purposes other than prosecution
under specified federal criminal statutes for fraud, perjury, and
related conduct. See 8 U. S. C. §§1324a(b)(5),
The legislative background of IRCA underscores
the fact that Congress made a deliberate choice not to impose crim-
inal penalties on aliens who seek, or engage in, unauthorized
employment. A commission established by Congress to study
immigration policy and to make recommen- dations concluded these
penalties would be “unnecessary and unworkable.”
U. S. Immigration Policy and the National Interest: The Final
Report and Recommendations of the Select Commission on Immigration
and Refugee Policy with Supplemental Views by Commissioners
65–66 (1981); see Pub. L. 95–412, §4, 92Stat. 907.
Proposals to make unauthorized work a criminal offense were debated
and discussed during the long process of drafting IRCA. See Brief
for Service Employees International Union et al. as Amici
9–12. But Congress rejected them. See,
119 Cong. Rec. 14184 (1973) (statement of Rep.
Dennis). In the end, IRCA’s framework reflects a considered
judgment that making criminals out of aliens engaged in
unauthorized work—aliens who already face the possibility of
employer exploitation because of their removable status—would
be inconsistent with federal policy and ob- jectives. See,
Hearings before the Subcommittee No. 1 of the
House Committee on the Judiciary, 92d Cong., 1st Sess., pt. 3,
pp. 919–920 (1971) (statement of Rep. Rodino, the
eventual sponsor of IRCA in the House of Representatives).
IRCA’s express preemption provision, which
in most instances bars States from imposing penalties on employers
of unauthorized aliens, is silent about whether additional
penalties may be imposed against the employees themselves. See 8
U. S. C. §1324a(h)(2); Whiting, supra,
___–___ (slip op., at 1–2). But the existence of an
“express pre-emption provisio[n] does not
ordinary working of conflict pre-emption principles” or
impose a “special burden” that would make it more
difficult to establish the preemption of laws falling outside the
v. American Honda Motor Co.
, 529 U.S.
, 869–872 (2000); see Sprietsma
, 537 U.S.
, 65 (2002).
The ordinary principles of preemption include
the well-settled proposition that a state law is preempted where it
“stands as an obstacle to the accomplishment and exe- cution
of the full purposes and objectives of Congress.”
, 312 U. S., at 67. Under §5(C) of S. B.
1070, Arizona law would interfere with the careful balance struck
by Congress with respect to unauthorized employment of aliens.
Although §5(C) attempts to achieve one of the same goals as
federal law—the deterrence of unlawful employment—it
involves a conflict in the method of enforcement. The Court has
recognized that a “[c]onflict in technique can be fully as
disruptive to the system Congress enacted as conflict in overt
policy.” Motor Coach Employees
, 287 (1971). The correct instruction to draw from the text,
structure, and history of IRCA is that Congress decided it would be
inappropriate to impose criminal penalties on aliens who seek or
engage in unauthorized employment. It follows that a state law to
the contrary is an obstacle to the regulatory system Congress
chose. See Puerto Rico Dept. of Con- sumer Affairs
ISLA Petroleum Corp.
, 485 U.S.
, 503 (1988) (“Where a comprehensive federal scheme
intentionally leaves a portion of the regulated field without
the pre-emptive inference can be
drawn—not from federal inaction alone, but from inaction
joined with action”). Section 5(C) is preempted by federal
Section 6 of S. B. 1070 provides that a state
officer, “without a warrant, may arrest a person if the
officer has probable cause to believe . . . [the person]
has committed any public offense that makes [him] removable from
the United States.” Ariz. Rev. Stat. Ann.
§13–3883(A)(5) (West Supp. 2011). The United States
argues that arrests authorized by this statute would be an obstacle
to the removal system Congress created.
As a general rule, it is not a crime for a
removable alien to remain present in the United States. See
, 468 U.S.
, 1038 (1984). If the police stop someone based on nothing
more than possible removability, the usual predicate for an arrest
is absent. When an alien is suspected of being removable, a federal
official issues an administrative document called a Notice to Ap-
pear. See 8 U. S. C. §1229(a); 8 CFR §239.1(a)
(2012). The form does not authorize an arrest. Instead, it gives
the alien information about the proceedings, including the time and
date of the removal hearing. See 8 U. S. C.
§1229(a)(1). If an alien fails to appear, an in
order may direct removal. §1229a(5)(A).
The federal statutory structure instructs when
it is ap- propriate to arrest an alien during the removal process.
For example, the Attorney General can exercise discretion to issue
a warrant for an alien’s arrest and detention “pending
a decision on whether the alien is to be removed from the United
States.” 8 U. S. C. §1226(a); see Memorandum
from John Morton, Director, ICE, to All Field Office Directors et
al., Exercising Prosecutorial Discretion Consistent with the Civil
Immigration Enforcement Priorities of the Agency for the
Apprehension, Detention, and Removal of Aliens (June 17, 2011)
(hereinafter 2011 ICE Memorandum) (describing factors informing
this and re- lated decisions). And if an alien is ordered removed
after a hearing, the Attorney General will issue a warrant. See 8
CFR §241.2(a)(1). In both instances, the warrants are executed
by federal officers who have received training in the enforcement
of immigration law. See §§241.2(b), 287.5(e)(3). If no
federal warrant has been issued, those officers have more limited
authority. See 8 U. S. C. §1357(a). They may arrest
an alien for being “in the United States in violation of any
[immigration] law or regula- tion,” for example, but only
where the alien “is likely to escape before a warrant can be
Section 6 attempts to provide state officers
even greater authority to arrest aliens on the basis of possible
removability than Congress has given to trained federal immi-
gration officers. Under state law, officers who believe an alien is
removable by reason of some “public offense” would have
the power to conduct an arrest on that basis regardless of whether
a federal warrant has issued or the alien is likely to escape. This
state authority could be exercised without any input from the
Federal Government about whether an arrest is warranted in a
particular case. This would allow the State to achieve its own
immigra- tion policy. The result could be unnecessary harassment of
some aliens (for instance, a veteran, college student, or someone
assisting with a criminal investigation) whom federal officials
determine should not be removed.
This is not the system Congress created. Federal
law specifies limited circumstances in which state officers may
perform the functions of an immigration officer. A principal
example is when the Attorney General has granted that authority to
specific officers in a formal agreement with a state or local
government. See §1357(g)(1); see also §1103(a)(10)
(authority may be extended in the event of an “imminent mass
influx of aliens off the coast of the United States”);
§1252c (authority to arrest in specific circumstance after
consultation with the Federal Government); §1324(c) (authority
to arrest for bringing in and harboring certain aliens). Officers
covered by these agreements are subject to the Attorney
General’s direction and super- vision. §1357(g)(3).
There are significant complexities involved in enforcing federal
immigration law, including the determination whether a person is
removable. See Padilla
, 559 U. S.
___, ___–___ (2010) (Alito, J., concurring in judgment) (slip
op., at 4–7). As a result, the agreements reached with the
Attorney General must contain written certification that officers
have received adequate training to carry out the duties of an
immigration officer. See §1357(g)(2); cf. 8 CFR
§§287.5(c) (ar- rest power contingent on training),
287.1(g) (defining the training).
By authorizing state officers to decide whether
an alien should be detained for being removable, §6 violates
the principle that the removal process is entrusted to the
discretion of the Federal Government. See, e.g., Reno
v. American-Arab Anti-Discrimination Comm., 525 U.S.
, 483–484 (1999); see also Brief for Former INS
Commissioners 8–13. A decision on removability requires a
determination whether it is appropriate to allow a foreign national
to continue living in the United States. Decisions of this nature
touch on foreign relations and must be made with one voice. See
v. Immigration and Customs Enforcement
, 348 (2005) (“Removal decisions, including the
selection of a removed alien’s destination, may implicate
[the Nation’s] relations with foreign powers and require
consideration of changing political and economic
circumstances” (internal quotation marks omitted)); see also
, 347 U.S.
, 531 (1954) (“Policies pertaining to the entry of
aliens and their right to remain here are . . . entrusted
exclusively to Congress . . .”); Truax
, 239 U.S.
, 42 (1915) (“The authority to control
immigration—to admit or exclude aliens—is vested solely
in the Federal Government”).
In defense of §6, Arizona notes a federal
statute permitting state officers to “cooperate with the
Attorney General in the identification, apprehension, detention, or
removal of aliens not lawfully present in the United States.”
8 U. S. C. §1357(g)(10)(B). There may be some
ambiguity as to what constitutes cooperation under the federal law;
but no coherent understanding of the term would incorporate the
unilateral decision of state officers to arrest an alien for being
removable absent any request, approval, or other instruction from
the Federal Government. The Department of Homeland Security gives
examples of what would constitute cooperation under federal law.
These include situations where States participate in a joint task
force with federal officers, provide operational support in
executing a warrant, or allow federal immigration officials to gain
access to detainees held in state facilities. See Dept. of Homeland
Security, Guidance on State and Local Governments’ Assistance
in Immigration Enforcement and Related Matters 13–14 (2011),
online at http:// www.dhs.gov/files/resources/immigration.shtm (all
Internet materials as visited June 21, 2012, and available in Clerk
of Court’s case file). State officials can also assist the
Federal Government by responding to requests for information about
when an alien will be released from their custody. See
§1357(d). But the unilateral state action to detain authorized
by §6 goes far beyond these measures, defeating any need for
Congress has put in place a system in which
state officers may not make warrantless arrests of aliens based on
possible removability except in specific, limited circumstances. By
nonetheless authorizing state and local offi- cers to engage in
these enforcement activities as a general matter, §6 creates
an obstacle to the full purposes and objectives of Congress. See
, 312 U. S., at 67. Section 6 is preempted by
Section 2(B) of S. B. 1070 requires state
officers to make a “reasonable attempt . . . to
determine the immigration status” of any person they stop,
detain, or arrest on some other legitimate basis if
“reasonable suspicion exists that the person is an alien and
is unlawfully present in the United States.” Ariz. Rev. Stat.
Ann. §11–1051(B) (West 2012). The law also provides that
“[a]ny person who is arrested shall have the person’s
immigration status determined before the person is released.”
The accepted way to perform these status checks is to
contact ICE, which maintains a database of immigration records.
Three limits are built into the state provision.
First, a detainee is presumed not to be an alien unlawfully present
in the United States if he or she provides a valid Arizona
driver’s license or similar identification. Second, officers
“may not consider race, color or national origin
. . . except to the extent permitted by the United States
[and] Ari- zona Constitution[s].” Ibid.
provisions must be “implemented in a manner consistent with
federal law regulating immigration, protecting the civil rights of
all persons and respecting the privileges and immunities of United
States citizens.” §11–1051(L) (West 2012).
The United States and its amici
that, even with these limits, the State’s verification
requirements pose an obstacle to the framework Congress put in
place. The first concern is the mandatory nature of the status
checks. The second is the possibility of prolonged detention while
the checks are being performed.
Consultation between federal and state
officials is an important feature of the immigration system.
Congress has made clear that no formal agreement or special
training needs to be in place for state officers to
“communicate with the [Federal Government] regarding the
immigration status of any individual, including reporting knowledge
that a particular alien is not lawfully present in the United
States.” 8 U. S. C. §1357(g)(10)(A). And
Congress has obligated ICE to respond to any request made by state
officials for verification of a person’s citizenship or im-
migration status. See §1373(c); see also §1226(d)(1)(A)
(requiring a system for determining whether individuals arrested
for aggravated felonies are aliens). ICE’s Law Enforcement
Support Center operates “24 hours a day, seven days a week,
365 days a year” and provides, among other things,
“immigration status, identity information and real-time
assistance to local, state and federal law enforcement
agencies.” ICE, Fact Sheet: Law Enforcement Support Center
(May 29, 2012), online at http://
www.ice.gov/news/library/factsheets/lesc.htm. LESC responded to
more than one million requests for information in 2009 alone. App.
The United States argues that making status
verification mandatory interferes with the federal immigration
scheme. It is true that §2(B) does not allow state officers to
consider federal enforcement priorities in deciding whether to
contact ICE about someone they have detained. See Brief for United
States 47–50. In other words, the officers must make an
inquiry even in cases where it seems unlikely that the Attorney
General would have the alien removed. This might be the case, for
example, when an alien is an elderly veteran with significant and
longstanding ties to the community. See 2011 ICE Memorandum
4–5 (mentioning these factors as relevant).
Congress has done nothing to suggest it is
inappropriate to communicate with ICE in these situations, however.
Indeed, it has encouraged the sharing of information about possible
immigration violations. See 8 U. S. C. §1357(g)
(10)(A). A federal statute regulating the public benefits provided
to qualified aliens in fact instructs that “no State or local
government entity may be prohibited, or in any way restricted, from
sending to or receiving from [ICE] information regarding the
immigration status, lawful or unlawful, of an alien in the United
States.” §1644. The federal scheme thus leaves room for
a policy requiring state officials to contact ICE as a routine
matter. Cf. Whiting
, 563 U. S., at ___–___ (slip
op., at 23–24) (rejecting argument that federal law preempted
Arizona’s requirement that employers determine whether
employees were eligible to work through the federal E-Verify system
where the Federal Government had encouraged its use).
Some who support the challenge to §2(B)
argue that, in practice, state officers will be required to delay
the release of some detainees for no reason other than to verify
their immigration status. See, e.g.,
Brief for Former
Arizona Attorney General Terry Goddard et al. as Amici
37, n. 49. Detaining individuals solely to verify
their immigration status would raise constitutional concerns. See,
, 555 U.S.
, 333 (2009); Illinois
, 543 U.S.
, 407 (2005) (“A seizure that is justified solely by
the interest in issuing a warning ticket to the driver can become
unlawful if it is prolonged beyond the time reasonably required to
complete that mission”). And it would disrupt the federal
framework to put state officers in the position of holding aliens
in custody for possible unlawful presence without federal direction
and supervision. Cf. Part IV–C, supra
Ari- zona may not authorize warrantless arrests on the basis of
removability). The program put in place by Congress does not allow
state or local officers to adopt this enforcement mechanism.
But §2(B) could be read to avoid these
concerns. To take one example, a person might be stopped for
jaywalking in Tucson and be unable to produce identification. The
first sentence of §2(B) instructs officers to make a
“reasonable” attempt to verify his immigration status
with ICE if there is reasonable suspicion that his presence in the
United States is unlawful. The state courts may conclude that,
unless the person continues to be suspected of some crime for which
he may be detained by state officers, it would not be reasonable to
prolong the stop for the immigration inquiry. See Reply Brief for
Petitioners 12, n. 4 (“[Section 2(B)] does not require
the verification be completed during the stop or detention if that
is not reasonable or practicable”); cf. Muehler
, 544 U.S.
, 101 (2005) (finding no Fourth Amendment violation where
questioning about immigration status did not prolong a stop).
To take another example, a person might be held
pending release on a charge of driving under the influence of
alcohol. As this goes beyond a mere stop, the arrestee (unlike the
jaywalker) would appear to be subject to the categorical
requirement in the second sentence of §2(B) that “[a]ny
person who is arrested shall have the person’s immigration
status determined before [he] is released.” State courts may
read this as an instruction to initiate a status check every time
someone is arrested, or in some subset of those cases, rather than
as a command to hold the person until the check is complete no
matter the circumstances. Even if the law is read as an instruction
to complete a check while the person is in custody, moreover, it is
not clear at this stage and on this record that the verification
process would result in prolonged detention. However the law is
interpreted, if §2(B) only requires state officers to conduct
a status check during the course of an authorized, lawful detention
or after a detainee has been released, the provision likely would
survive pre- emption—at least absent some showing that it has
other consequences that are adverse to federal law and its
objectives. There is no need in this case to address whether
reasonable suspicion of illegal entry or another immigration crime
would be a legitimate basis for prolonging a detention, or whether
this too would be preempted by federal law. See, e.g., United
v. Di Re
, 332 U.S.
, 589 (1948) (authority of state officers to make arrests
for federal crimes is, absent federal statutory instruction, a
matter of state law); Gonzales
, 722 F.2d
468, 475–476 (CA9 1983) (concluding that Arizona officers
have authority to enforce the criminal provisions of federal
immigration law), overruled on other grounds in
v. de la Vina
199 F.3d 1037
The nature and timing of this case counsel
caution in evaluating the validity of §2(B). The Federal
Government has brought suit against a sovereign State to challenge
the provision even before the law has gone into effect. There is a
basic uncertainty about what the law means and how it will be
enforced. At this stage, without the benefit of a definitive
interpretation from the state courts, it would be inappropriate to
assume §2(B) will be construed in a way that creates a
conflict with federal law. Cf. Fox
, 277 (1915) (“So far as statutes fairly may be
construed in such a way as to avoid doubtful constitutional
questions they should be so construed; and it is to be presumed
that state laws will be construed in that way by the state
courts” (citation omitted)). As a result, the United States
cannot prevail in its current challenge. See Huron Portland
, 362 U.S.
, 446 (1960) (“To hold otherwise would be to ignore
the teaching of this Court’s decisions which enjoin seeking
out conflicts between state and federal regulation where none
clearly exists”). This opinion does not foreclose other
preemption and constitutional challenges to the law as interpreted
and applied after it goes into effect.
Immigration policy shapes the destiny of the
Nation. On May 24, 2012, at one of this Nation’s most
distinguished museums of history, a dozen immigrants stood before
the tattered flag that inspired Francis Scott Key to write the
National Anthem. There they took the oath to become American
citizens. The Smithsonian, News Release, Smithsonian Citizenship
Ceremony Welcomes a Dozen New Americans (May 24, 2012), online at
http://newsdesk.si.edu/releases. These naturalization cere- monies
bring together men and women of different ori- gins who now share a
common destiny. They swear a common oath to renounce fidelity to
foreign princes, to defend the Constitution, and to bear arms on
behalf of the country when required by law. 8 CFR §337.1(a)
(2012). The history of the United States is in part made of the
stories, talents, and lasting contributions of those who crossed
oceans and deserts to come here.
The National Government has significant power to
regulate immigration. With power comes responsibility, and the
sound exercise of national power over immigration depends on the
Nation’s meeting its responsibility to base its laws on a
political will informed by searching, thoughtful, rational civic
discourse. Arizona may have understandable frustrations with the
problems caused by illegal immigration while that process
continues, but the State may not pursue policies that undermine
* * *
The United States has established that
§§3, 5(C), and 6 of S. B. 1070 are preempted. It was
improper, however, to enjoin §2(B) before the state courts had
an opportunity to construe it and without some showing that
enforcement of the provision in fact conflicts with federal
immigration law and its objectives.
The judgment of the Court of Appeals for the
Ninth Circuit is affirmed in part and reversed in part. The case is
remanded for further proceedings consistent with this opinion.
It is so ordered.
Justice Kagan took no part in the consideration
or decision of this case.