Cite as: 

 (2025)            1




SUPREME COURT OF THE UNITED STATES
                          _________________

                           No. 25A443
                          _________________


  DONALD J. TRUMP, PRESIDENT OF THE UNITED
       STATES, ET AL. v. ILLINOIS, ET AL.
                 ON APPLICATION FOR STAY
                      [December 23, 2025]

   Federal immigration-enforcement efforts have encoun-
tered significant resistance, as well as some violence, in
Chicago. According to the Government, federal officers
have been obstructed, threatened, and assaulted as they at-
tempt to perform their duties. The Government also alleges
that an Immigration and Customs Enforcement processing
facility in Broadview, Illinois, has been the site of frequent
and sometimes violent protests, damaging federal property
and threatening the safety of federal officers. These at-
tacks, the Government says, have greatly impeded its ef-
forts to enforce the immigration laws.
   On October 4, 2025, the President called 300 members of
the Illinois National Guard into active federal service to
protect federal personnel and property in Illinois, particu-
larly in and around Chicago. The following day, members
of the Texas National Guard were also federalized and sent
to Chicago. In calling forth the Guard, the President relied
on 

(3), which empowers him to federalize
members of the Guard if he is “unable with the regular
forces to execute the laws of the United States.”
   The United States District Court for the Northern Dis-
trict of Illinois entered a temporary restraining order bar-
ring the federalization and deployment of the Guard in Illi-
nois. The Seventh Circuit denied in relevant part the
Government’s motion for a stay, permitting the Guard to
2                    TRUMP v. ILLINOIS



remain federalized within Illinois but maintaining the bar
on deployment.
   The Government asked this Court to stay the District
Court’s order. After the response and reply were filed,
JUSTICE BARRETT referred the application to the Court. We
directed the parties to file supplemental letter briefs on an
issue that the District Court had addressed but the parties’
initial briefs had not: the meaning of the term “regular
forces” in §12406(3). In its supplemental brief, the Govern-
ment argues that the term refers to civilian law enforce-
ment officers, such as those employed by Immigration and
Customs Enforcement or the Federal Protective Service.
Respondents, echoing the District Court, maintain that the
term refers to the regular forces of the United States mili-
tary.
   We conclude that the term “regular forces” in §12406(3)
likely refers to the regular forces of the United States mili-
tary. This interpretation means that to call the Guard into
active federal service under §12406(3), the President must
be “unable” with the regular military “to execute the laws of
the United States.” Because the statute requires an assess-
ment of the military’s ability to execute the laws, it likely
applies only where the military could legally execute the
laws. Such circumstances are exceptional: Under the Posse
Comitatus Act, the military is prohibited from “execut[ing]
the laws” “except in cases and under circumstances ex-
pressly authorized by the Constitution or Act of Congress.”

. So before the President can federalize
the Guard under §12406(3), he likely must have statutory
or constitutional authority to execute the laws with the reg-
ular military and must be “unable” with those forces to per-
form that function.
   At this preliminary stage, the Government has failed to
identify a source of authority that would allow the military
to execute the laws in Illinois. The President has not in-
voked a statute that provides an exception to the Posse
                  Cite as: 

 (2025)            3

             KAVANAUGH, J., concurring in judgment

Comitatus Act. Instead, he relies on inherent constitu-
tional authority that, according to the Government, allows
him to use the military to protect federal personnel and
property. But the Government also claims—consistent
with the longstanding view of the Executive Branch—that
performing such protective functions does not constitute
“execut[ing] the laws” within the meaning of the Posse
Comitatus Act. See Supp. Letter Reply Brief for Applicants
8; 1 Supp. Op. OLC 343, n. 1 (1971) (collecting sources). If
that is correct, it is hard to see how performing those func-
tions could constitute “execut[ing] the laws” under
§12406(3). See Azar v. Allina Health Services, 

 (2019) (“This Court does not lightly assume that
Congress silently attaches different meanings to the same
term in the same or related statutes”). Thus, at least in this
posture, the Government has not carried its burden to show
that §12406(3) permits the President to federalize the
Guard in the exercise of inherent authority to protect fed-
eral personnel and property in Illinois. We need not and do
not address the reviewability of findings made by the Pres-
ident under §12406(3) or any other statute.
   The application for stay is denied.
   JUSTICE KAVANAUGH, concurring in the judgment.
   To protect federal personnel and property in Illinois, the
President federalized about 300 National Guard members.
The State of Illinois sued, and as relevant here, the District
Court barred the President from deploying the Guard.
After the Seventh Circuit declined to stay the District
Court’s order, the Government applied to this Court for a
stay. I agree with the Court’s decision to deny the
Government’s application for a stay, but I would do so on
narrower grounds.
   To federalize the National Guard, the President first
must determine that he is “unable with the regular forces
to execute the laws of the United States.” 10 U. S. C.
4                        TRUMP v. ILLINOIS

                KAVANAUGH, J., concurring in judgment

§12406(3). In my view, the statutory term “regular forces”
likely refers to the U. S. military, not to federal civilian law
enforcement officers. On the current record, however, it
does not appear that the President has yet made the
statutorily required determination that he is “unable” with
the U. S. military, as distinct from federal civilian law
enforcement officers, to ensure the execution of federal law
in Illinois. (The President of course would have great
discretion to make that determination, as the State itself
acknowledges.        See Supp. Letter Reply Brief for
Respondents 7; Department of Navy v. Egan, 

,
529–530 (1988).)
   On that narrow ground, I would deny the Government’s
application for a stay. We need not decide more, so I would
not decide more.
   The Court goes further. The Court starts by concluding
that “regular forces” means the U. S. military. (As noted
above, I agree with that initial point.) From there, however,
the Court conducts a complicated and debatable statutory
analysis. The Court says that under the Government’s
argument, “it is hard to see how performing those
functions”—that is, protecting federal personnel and
property—“could constitute ‘execut[ing] the laws’ under
§12406(3).” Ante, at 3. On that premise, the Court further
states that “at least in this posture, the Government has
not carried its burden to show that §12406(3) permits the
President to federalize the Guard in the exercise of inherent
authority to protect federal personnel and property in
Illinois,” ante, at 3—even if the President finds that he is
“unable” with the U. S. military to protect federal personnel
and property from harm.1


——————
  1 The statute also separately authorizes the President to federalize the

National Guard if there is an “invasion” or “rebellion.” 

(1)–(2).
                      Cite as: 

 (2025)                      5

                 KAVANAUGH, J., concurring in judgment

  The Court’s legal interpretation, as I understand it, could
lead to potentially significant implications for future crises
that we cannot now foresee. Consider a hypothetical
example. Suppose a mob rapidly gathers outside the U. S.
Courthouse in Philadelphia in response to an unpopular
decision (or to influence the outcome of a pending matter).
Suppose also that the mob is threatening to storm the
courthouse and attack the federal judges, prosecutors, and
other personnel inside, and to damage or burn down the
building, thereby preventing the execution of federal law.
Suppose further that U. S. military forces cannot readily
mobilize to deploy to the site in time, that the local police
and federal court security officers are outnumbered, and
that the President wants to federalize National Guard units
to protect the courthouse and the judges, prosecutors, and
other personnel. Under the Court’s order today, even in
those circumstances the President presumably could not
federalize the National Guard under §12406(3).2
  Of course, that kind of hypothetical scenario does not
often arise, and we can hope that it will not arise in the
future. But the potential consequences, combined with the
——————
   2 As I read it, the Court’s opinion does not address the President’s

authority under the Insurrection Act. See 

, 253.
Moreover, the Court’s opinion does not address or purport to disturb the
President’s long-asserted Article II authority to use the U. S. military (as
distinct from the National Guard) to protect federal personnel and
property and thereby ensure the execution of federal law. See 1 Supp.
Op. OLC 343 (1971) (W. Rehnquist). As Professor Goldsmith has
succinctly explained: “The protective power is the president’s inherent or
independent Article II power to protect federal personnel, property, and
functions. The key point is that the president can assert the protective
power without reliance on Section 12406. He can deploy regular armed
forces without any need to federalize the Guard. Presidents often have.”
J. Goldsmith, President Trump Holds the Legal Cards on the Use of the
Military in the Domestic Sphere, Executive Functions (Oct. 8, 2025).
One apparent ramification of the Court’s opinion is that it could cause
the President to use the U. S. military more than the National Guard to
protect federal personnel and property in the United States.
6                         TRUMP v. ILLINOIS

                KAVANAUGH, J., concurring in judgment

novelty and difficulty of the statutory issues addressed by
the Court, underscore why I would not opine more broadly
than necessary to resolve this application.3
   Before addressing those challenging and far-reaching
statutory questions at this stage of the case, I would have
at least invited further briefing and possibly also held oral
argument, either on the application itself or by granting
certiorari before judgment, akin to what the Court has done
on several recent occasions. See Trump v. CASA, Inc., 

 (2025); Ohio v. EPA, 

 (2024);
National Federation of Independent Business v. OSHA, 

 (2022). As I have stated with respect to previous
interim applications of substantial import and difficulty,
the Court can help guard against mistakes or
misjudgments by employing additional process when
sufficient time is available—recognizing, of course, that
time will not always be available. See Trump v. Boyle, 

 (2025) (KAVANAUGH, J., concurring); Trump v.
CASA, Inc., 606 U. S., at 876 (KAVANAUGH, J., concurring);
A.A.R.P. v. Trump, 

 (2025) (KAVANAUGH,
J., concurring); Labrador v. Poe, 

, 1127–1129
(2024) (KAVANAUGH, J., concurring).4
——————
   3 The Court’s decision reflects only likely legal conclusions and comes

at a “preliminary stage.” Ante, at 2. That said, the decision will
presumably be a form of precedent throughout the Federal Judiciary that
requires a temporary injunction (either a preliminary injunction or an
injunction pending appeal or certiorari) in like circumstances, unless and
until this Court reaches a contrary conclusion. See Trump v. Boyle, 

 (2025); Trump v. CASA, Inc., 

, 873 (2025)
(KAVANAUGH, J., concurring). The Court also emphasizes that the
Government has failed to carry its “burden.” Ante, at 3. In this context,
that statement seems to convey the truisms that, in future litigation, the
Court could reconsider its view of the law or the Government might seek
to advance new or different arguments.
   4 The State’s opposition to deployment of the National Guard appears

to stem in part from the State’s underlying objections to the activities of
federal immigration officers when they make immigration stops and
                      Cite as: 

 (2025)                     7

                KAVANAUGH, J., concurring in judgment

  In sum, I vote to deny the application but would do so on
narrow grounds and, at this time, would not reach the
broader statutory issues addressed by the Court.




——————
arrests in Illinois. The State and the Government disagree about
whether the immigration officers have violated the Constitution in
making certain immigration stops and arrests. The basic constitutional
rules governing that dispute are longstanding and clear: The Fourth
Amendment requires that immigration stops must be based on
reasonable suspicion of illegal presence, stops must be brief, arrests must
be based on probable cause, and officers must not employ excessive force.
Moreover, the officers must not make interior immigration stops or
arrests based on race or ethnicity. Cf. Whren v. United States, 

 (1996) (“[T]he Constitution prohibits selective enforcement of
the law based on considerations such as race”). This application does not
require us to delve into the parties’ underlying dispute and to determine
whether any particular immigration encounter or series of encounters in
Illinois has violated those basic constitutional principles.
                 Cite as: 

 (2025)            1

                     ALITO, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                          No. 25A443
                         _________________


  DONALD J. TRUMP, PRESIDENT OF THE UNITED
       STATES, ET AL. v. ILLINOIS, ET AL.
                 ON APPLICATION FOR STAY
                     [December 23, 2025]


  JUSTICE ALITO, with whom JUSTICE THOMAS joins, dis-
senting.
  “ ‘In our adversarial system of adjudication, we follow the
principle of party presentation.’ ” Clark v. Sweeney, 

, ___ (2025) (per curiam) (slip op., at 2) (quoting
United States v. Sineneng-Smith, 

(2020)). If a party passes up what seems to us a promising
argument, we do not assume the role of advocate. Instead,
we normally decide the questions that the parties choose to
present.
  In this case, the Court has unnecessarily and unwisely
departed from standard practice. It raised an argument
that respondents waived below, and it now rules in re-
spondents’ favor on that ground. To make matters worse,
the Court reaches out and expresses tentative views on
other highly important issues on which there is no relevant
judicial precedent and on which we have received scant
briefing and no oral argument.
  First, the Court suggests that the principal statutory pro-
vision involved in the case, 

(3), contains
a restriction that has no grounding in the statutory text,
namely, that “unable with the regular forces to execute the
laws of the United States” actually means “unable with the
regular forces to execute the laws of the United States for
reasons other than the lack of lawful authority to do
2                     TRUMP v. ILLINOIS

                      ALITO, J., dissenting

so.” The Court in effect adds new language to the text Con-
gress enacted.
   Second, the Court implicitly suggests that §12406(3) does
not constitute an “Act of Congress” within the meaning of
that phrase in the Posse Comitatus Act. §1385. That is a
surprising conclusion, to say the least.
   Third, the Court expresses the tentative view that the
phrase “execute the laws of the United States” in §12406(3)
does not include “protective functions” so that even if the
National Guard is properly deployed under that provision,
it may not be given the task of preventing potentially lethal
attacks on civilian federal law enforcement officers or the
takeover or destruction of Government facilities. According
to the Court’s apparent reasoning, National Guard mem-
bers may enforce the immigration laws by, for example, ar-
resting and processing aliens, but they may not perform the
protective functions for which they are better suited. That,
too, is surprising.
   On top of all this, the Court fails to explain why the Pres-
ident’s inherent constitutional authority to protect federal
officers and property is not sufficient to justify the use of
National Guard members in the relevant area for precisely
that purpose.
   I am not prepared at this point to express a definite view
on these questions, but I have serious doubts about the cor-
rectness of the Court’s views. And I strongly disagree with
the manner in which the Court has disposed of this appli-
cation.
                            I
                            A
  The key statutory provision in this case, 

(3), provides in relevant part that “[w]henever . . .
the President is unable with the regular forces to execute
the laws of the United States,” he “may call into Federal
service members and units of the National Guard of any
                  Cite as: 

 (2025)             3

                      ALITO, J., dissenting

State in such numbers as he considers necessary to . . . ex-
ecute those laws.”
   In the lower courts, the parties agreed that the phrase
“regular forces” means civilian federal law enforcement of-
ficers, not military service members. Respondents explic-
itly adopted this position in the District Court. That court
disagreed, but when the Government challenged this hold-
ing in the Seventh Circuit, respondents declined to defend
the lower court’s interpretation, and the Seventh Circuit
did not reach the issue. The Government’s stay application
in this Court asserted that any defense of the District
Court’s interpretation had been waived, and respondents
did not dispute either that assertion or the correctness of
the Government’s contention that “regular forces” means
federal civilian officers. Thus, the argument that “regular
forces” means the military was either waived or forfeited
three times over.
   Ignoring this history, the Court ordered the parties to file
supplemental briefs on the meaning of “regular forces.” Re-
spondents “[u]nderstandably . . . rode with an argument
suggested by” the Court and argued, for the first time and
contrary to their position below, that the “regular forces”
means the military. Sineneng-Smith, 

.
The majority now accepts this eleventh-hour argument.
“Nevermind that [respondents] had presented a contrary
theory of the case in the District Court.” 

. For
the Court, respondents’ “own arguments, differently di-
rected, fell by the wayside, for they did not mesh with” the
Court’s own “theory of the case.” 

.
   We should decide this application based on the “party-
presented controversy.” 

. That controversy cen-
tered on the District Court’s holding that, contrary to the
President’s determination, civilian federal law enforcement
officers were in fact able to execute federal laws in the Chi-
cago area. If the Court has doubts about the parties’ inter-
pretation of the phrase “regular forces,” it could assume for
4                    TRUMP v. ILLINOIS

                      ALITO, J., dissenting

the sake of argument that the parties’ interpretation was
correct and proceed on that basis. The Court has done that
on many occasions. E.g., Warner Chappell Music, Inc. v.
Nealy, 

, 371 (2024) (assuming there is a dis-
covery rule for copyright claims); Financial Oversight and
Management Bd. for P. R. v. Centro de Periodismo Investi-
gativo, Inc., 

, 345, 346 (2023) (“assum[ing]
without deciding that Puerto Rico is immune from suit in
federal district court and that [a financial oversight board]
partakes of that immunity” because respondent “never ar-
gued” otherwise in the courts below); Wisconsin Legislature
v. Wisconsin Elections Comm’n, 

 (2022)
(per curiam) (assuming without deciding that complying
with the Voting Rights Act is a compelling interest);
McDonough v. Smith, 

, 115 (2019) (assuming
without deciding that a due process fabricated-evidence
claim may be asserted under Rev. Stat. §1979, 

).
  In this case, the Court has no good reason to stray beyond
the issues that the parties chose to present, and based on
those arguments, the Court should grant the application.
There is no basis for rejecting the President’s determination
that he was unable to execute the federal immigration laws
using the civilian law enforcement resources at his com-
mand. In concluding otherwise, the District Court likely
committed both legal and factual error.
                              B
                               1
  I will begin with the District Court’s understanding of the
applicable law. The District Court held that a President is
“unable” to execute federal law within the meaning of 

 only if he is literally “incapable” of execut-
ing the law with the regular forces. App. to Application 23a.
That interpretation is implausible. If the term “regular
forces” means federal civilian law enforcement officers, that
                  Cite as: 

 (2025)            5

                      ALITO, J., dissenting

interpretation would mean that the President would have
to conclude that the immigration laws could not be enforced
in Illinois even if all other federal law enforcement activi-
ties were put on hold and every federal law enforcement of-
ficer in the country—including every FBI, DEA, Secret Ser-
vice, and ATF agent, every postal inspector and deputy
marshal, and all the law enforcement officers employed by
other agencies—were transferred to that area and assigned
that task.
   The District Court’s interpretation would lead to even
more outlandish results if “regular forces” means the mili-
tary. In that case, a President could not call up the Na-
tional Guard to execute the laws in one locale unless all the
Nation’s military forces, if transferred to the area in ques-
tion, would be incapable of executing the laws.
   A less extreme interpretation of “unable” is much more
reasonable and consistent with the way the term is com-
monly used. In everyday speech, a person may say that he
or she is “unable” to perform an act simply because the ad-
verse consequences of performing that act would be unac-
ceptable. For example, an attorney might tell a trial court
judge that he or she is “unable” to start a trial on a partic-
ular day because the attorney is scheduled to argue a case
in this Court on that date and no other attorney could pre-
pare for the argument in time. That attorney would be ca-
pable of showing up for the trial on the day in question, but
the attorney’s use of the term “unable” would be entirely
natural.
   The District Court’s interpretation of “unable” was im-
plausible for an additional reason: It seems to prohibit de-
ployment of the National Guard unless the President could
not execute the laws to even the slightest extent. The Dis-
trict Court took what it termed “a binary approach: ability
or not, capability or not.” Id., at 68a. As the Ninth Circuit
has explained, however, “Section §12406(3) cannot plausi-
bly be read to mean that so long as some amount of
6                     TRUMP v. ILLINOIS

                      ALITO, J., dissenting

execution of the laws remains possible, the statute cannot
be invoked, regardless of how much execution of the laws
remains thwarted or how much personal danger federal
personnel face during operations.” Newsom v. Trump, 

 (2025). It is more reasonable to interpret
§12406(3) to means that a President is “unable” to execute
the laws when he is substantially impaired from doing so.
                                2
   The District Court also erred in refusing to afford any def-
erence to the President’s determination that calling up the
National Guard was needed to execute federal law. The
most directly relevant Supreme Court precedent suggests
that such a determination must be accepted by the courts.
In Martin v. Mott, 

 (1827), a militia mem-
ber argued, among other things, that the standard for call-
ing up the militia under the law in force at the time had not
been met. See Act of Feb. 28, 1795, 

. Section 1
of that law governed use of the militia when the country is
invaded or threatened with invasion, and §2, much like
§12406(3), authorized use of the militia when “the execu-
tion” of federal law is obstructed. Addressing the §1 stand-
ard, Justice Story’s opinion for the unanimous Court held
that “the authority to decide whether the exigency has
arisen . . . belongs exclusively to the President.” 

. “[H]is decision,” the Court held, “is conclusive,” and
therefore, application of the statute depends only on “his
own judgment of the facts.” 

; see also Luther
v. Borden, 

, 43–45 (1849) (reaffirming the holding
in Martin and the unreviewability of the President’s deci-
sion to call up the militia).
   The District Court gave no weight to this precedent. It
saw Martin as a relic, viewed its express holding as limited
to the particular facts of the case, and thought it had been
superseded by more recent political-question decisions.
Such treatment of a Supreme Court precedent that has
                  Cite as: 

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                      ALITO, J., dissenting

never been overruled, narrowed, or questioned by this
Court was inappropriate. See Mallory v. Norfolk Southern
R. Co., 

, 136 (2023).
   Even if Martin does not dictate judicial acceptance of a
President’s decision to call up the National Guard, both
that precedent and a humble appreciation of the role of a
single federal judge surely demanded that such a Presiden-
tial determination be given a modicum of deference. The
District Court afforded none.
   For these reasons, the District Court appears to have mis-
understood what the law requires, and those legal errors
alone justify a stay.
                               C
   Once the proper legal framework is recognized, the Pres-
ident’s determination must almost certainly be sustained.
The Government’s declarations show that U. S. Immigra-
tion and Customs Enforcement (ICE) operations in and
around Chicago have been the target of unprecedented sab-
otage and violence since June of this year. Hundreds of ri-
oters have converged at the Department of Homeland Secu-
rity facility in Broadview, Illinois, the only intake and
processing center for ICE operations in the Chicago area.
These rioters have been organized, gathering offsite and ar-
riving in vans, then getting picked up several hours later
by vans returning with new rioters. They have arrived
armed with shields, gas masks, protective padding, and
other tools for physical combat. And they have blocked en-
try and exit at the ICE facility, physically assaulted person-
nel attempting to enter or leave work, significantly dam-
aged the building, and vandalized both Government and
personally owned vehicles.
   The resulting violence has endangered the lives of federal
personnel. Multiple rioters have been found with loaded
guns, some of them semi-automatic. Rioters have hit,
punched, and shoved officers; thrown bottles, rocks, and
8                     TRUMP v. ILLINOIS

                      ALITO, J., dissenting

tear gas canisters at officers; attempted to grab officers’
firearms and munitions; pulled gas masks and tear gas can-
isters off the officers’ uniforms; targeted officers with bull-
horns and whistles that can cause permanent hearing loss;
aimed strobe lights and lasers at officers’ faces; and shot
fireworks at officers. On more than a dozen occasions, one
rioter jumped on the hood of an incoming Government ve-
hicle, and another took up a position immediately behind
the vehicle. When the vehicle stopped, other rioters ran up
and slashed the vehicle’s tires. As of early October, more
than 30 federal officers had suffered injuries, and multiple
officers had been hospitalized.
   In a widely publicized event on October 4, a federal vehi-
cle carrying Border Patrol agents was boxed in on a public
road by 10 civilian vehicles, and 2 of those vehicles rammed
the Government vehicle. As the agents exited their vehicle,
one of the civilian vehicles was driven directly at an agent,
forcing the agent to fire in self-defense. Hundreds of rioters
then converged near the scene, throwing glass bottles and
other dangerous objects at the agents. A federal vehicle
sent to assist the besieged agents was itself rammed. Later
in the day, a federal van was surrounded by rioters who
slashed its tires, but no emergency assistance was available
because of damage done to other Government vehicles ear-
lier that day.
   Even when not on duty, federal officers have been tar-
geted. They have been followed to their homes and “doxed.”
Officers and their families have been threatened, and their
homes and vehicles have been vandalized. Criminal enter-
prises have offered bounties for kidnapping or murdering
immigration officers. More than 20 officers have had their
home addresses posted on social media, and posts have
called for officials to be shot and killed on sight.
   Local police departments have provided insufficient as-
sistance. When the October 4 ramming incident was re-
ported to the Chicago Police Department, an internal
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                     ALITO, J., dissenting

dispatch stated that “NO UNITS WILL RESPOND TO
THIS.” On September 13, when rioters threw rocks,
slashed tires, and poured flour into a federal vehicle’s gas
tank, ICE officers called the Broadview Police Department
three times to ask for assistance. The Broadview Police
never responded.
  In sum, injuries, threats, vandalism, and harassment
have significantly impaired efforts to execute the laws. The
agencies have had to reallocate resources from enforcing
the immigration laws to the provision of security for offic-
ers, the Broadview facility, and other Government prop-
erty. Even if the President’s assessment of the situation is
given no deference, these facts adequately show that federal
civilian offers were “unable to” execute the immigration
laws under what appears to be the correct understanding of
that standard.
                              D
   The District Court disagreed but gave no good reason for
doing so. Respondents, as the parties seeking interim re-
lief, bore the burden of proof. See Winter v. Natural Re-
sources Defense Council, Inc., 

 (2008). But
instead of evaluating whether respondents had borne their
burden, the District Court brushed aside the facts set out
in the Government’s declarations (many of which were un-
disputed) based on two perceived weaknesses in those dec-
larations.
   Neither of the District Court’s criticisms justified the
wholesale dismissal of the Government’s declarations. The
court’s first criticism concerned the failure of two declar-
ants to acknowledge that grand juries had declined to indict
three of the individuals whose arrests were mentioned in
the declarations. The court saw the declarants’ failure to
mention the grand juries’ actions as evidence of mendacity.
But the court did not take into account the dates on which
the declarations were filed and the dates on which the
10                   TRUMP v. ILLINOIS

                      ALITO, J., dissenting

grand juries declined to indict, and it did not find that the
declarants were aware of the grand juries’ actions. Unless
the declarants had such knowledge, however, there was no
ground for impugning their candor.
   Second, the court suggested that the same declarants’ de-
scriptions of the relevant events were exaggerated because
they had submitted similar declarations in another case in
which a different judge found that ICE officers had likely
violated protestors’ First Amendment rights. But again,
more would have to be known before accepting this criti-
cism. What we do know is that the cited order in the First
Amendment case did not make any credibility findings and
did not discuss the Government’s declarations at all, much
less find them false. See Chicago Headline Club v. Noem,
No. 1:25–cv–12173, (ND Ill., Oct. 9, 2025), ECF Doc. 43.
   For these reasons, the validity of the District Court’s two
criticisms is questionable, but even if they are taken at face
value, they cannot justify the court’s wholesale refusal to
credit the declarations’ uncontested description of serious
and continuous violence.
   Nor can the District Court’s decision be justified by con-
clusory statements in respondents’ declarations about the
capability of state and local law enforcement to provide pro-
tection. E.g., App. to Application 43a; Decl. of Major D.
Orseno, No. 1:25–cv–12174, (ND Ill., Oct. 6, 2025), ECF
Doc. 13–15. Such statements provided no reason to doubt
the occurrence of the incidents of violence described in the
Government’s declarations. And there is an obvious differ-
ence between the capabilities of state and local police and
their willingness to assist. Thus, even if we assume that a
Presidential determination under §12406(3) is reviewable
and not entitled to any special deference, the District Court
erred in refusing to credit the unrefuted facts offered by the
Government. And those facts provide more than enough
support for the President’s determination that he was
                  Cite as: 

 (2025)            11

                      ALITO, J., dissenting

unable to enforce federal law in the Chicago area using fed-
eral civilian law enforcement officers.
                               II
  Instead of abiding by the standard rule on party presen-
tation, the Court took it upon itself to raise the question
whether the parties’ understanding of “regular forces” was
correct. And taking a cue from this Court, respondents
abandoned their position below and switched to the argu-
ment that the phrase “regular forces” refers to the military,
not civilian federal law enforcement. The Court tentatively
agrees with respondents’ new argument, but even if that is
correct, it does not follow that the President exceeded his
lawful authority when he called the National Guard into
federal service to assist in executing federal law in Illinois.
                                A
   Regardless of how the term “regular forces” is defined, the
President appears to have complied with the requirements
of §12406(3). The provision asks whether the “President is
unable with the regular forces to execute the laws of the
United States.” And the President said unequivocally that
he had “determined that the regular forces of the United
States are not sufficient to ensure the laws of the United
States are faithfully executed . . . in Chicago.” Memoran-
dum for Secretary of War et al., No. 1:25–cv–12174 (ND
Ill.), ECF Doc. 62–1, pp. 16–17 (Presidential Memo). Not
only is this statement sufficient on its face, but under the
presumption of regularity, the Court must presume that
the President properly arrived at his determination. See
Martin, 12 Wheat., at 32–33 (“When the President exercises
an authority confided to him by law, the presumption is,
that it is exercised in pursuance of law”).
   The majority does not explain why the President’s decla-
ration falls short. Instead, it breezily concludes that a Pres-
ident’s inability to execute the law cannot be established
12                   TRUMP v. ILLINOIS

                      ALITO, J., dissenting

unless “the military could legally execute the laws.” Ante,
at 2 (emphasis added). In effect, the Court adds new lan-
guage to the statute so that it now requires that a President
be “unable with the regular forces to execute the laws of the
United States for reasons other than the lack of lawful
authority to do so.” We have no authority to add this new
language to the text Congress enacted.
   The sole requirement set out in the text of §12406(3) is
that the President must be “unable with the regular forces
to execute the laws of the United States.” That text says
nothing about the cause of the President’s inability to exe-
cute the laws, and in ordinary usage, it is common to say
that a person is “unable to” perform an act when the obsta-
cle is a rule of law. For example, it would be natural to say
that a person who is fully capable of operating a motor ve-
hicle is nevertheless “unable to” drive to work because his
or her license has been suspended. Or, to take one more
example, it would be natural to say that a federal district
court is “unable to” adjudicate a case in which the plaintiff
sues a citizen of the same State under state law. See 

. This use of the term “unable” would be en-
tirely appropriate even if the judge, as will almost certainly
be the case, is fully capable of handling such a case.
   By the same token, if we apply the ordinary meaning of
“unable to” in a case involving §12406(3), a President may
be “unable to” use the military to execute the laws due to
either practical or legal constraints.
                               B
   Even if §12406(3) contained the extra requirement that
the Court adds, there would be reasonable grounds for con-
cluding that the President had authority to take the actions
at issue. Indeed, the Court seems to acknowledge as much.
It notes that the President invokes his “inherent constitu-
tional authority . . . to use the military to protect federal
personnel and property,” ante, at 3, and it cites with
                     Cite as: 

 (2025)                    13

                          ALITO, J., dissenting

apparent approval a body of Office of Legal Counsel opin-
ions sanctioning this understanding of inherent Presiden-
tial power. Authority To Use Troops To Prevent Interfer-
ence With Federal Employees by Mayday Demonstrations
and Consequent Impairment of Government Functions, 1
Supp. Op. OLC 343, 343–344 (1971) (citing earlier opin-
ions); see also In re Neagle, 

, 58–59, 67 (1890)
(recognizing an inherent authority to protect federal
judges); In re Debs, 

 (1895) (recognizing
an inherent authority to protect highways for the passage
of interstate commerce and mail).
   That is what happened here: The President authorized
the National Guard to “perform those protective activities
that the Secretary of War determines are reasonably neces-
sary to ensure the execution of Federal law in Illinois, and
to protect Federal property in Illinois.” Presidential Memo.
17. Although the Court recognizes this inherent Presiden-
tial power, it does not explain why it is not sufficient to sat-
isfy the new element that the Court has added to
§12406(3).1
   The Court seems to suggest that the Posse Comitatus
Act, 

, stands in the way of what the Presi-
dent did here, but that is puzzling. Does the Court mean to
suggest that the Posse Comitatus Act somehow limited a
President’s inherent constitutional authority? That is cer-
tainly not Congress’s view. See 

(a)(4) (“[B]y
——————
  1 If §12406(3) is triggered only when a President determines that he is

unable to execute the law by using the military, it is not easy to see how
a court could assess and reject such a determination. As discussed, ina-
bility under §12406 should likely be interpreted to require no more than
serious detrimental consequences, and therefore the statutory predicate
should likely be regarded as satisfied whenever the deployment of mili-
tary units for the purpose of executing the laws at home would have such
consequences. Assessing the impact of such a deployment would require
a survey and analysis of all the Nation’s military needs, and only a Pres-
ident and those under his command are equipped to make such an as-
sessment.
14                        TRUMP v. ILLINOIS

                          ALITO, J., dissenting

its express terms, the Posse Comitatus Act is not a complete
barrier to the use of the Armed Forces for a range of domes-
tic purposes, including law enforcement functions, when
the use of the Armed Forces is authorized by Act of Con-
gress or the President determines that the use of the Armed
Forces is required to fulfill the President’s obligations un-
der the Constitution to respond promptly in time of war,
insurrection, or other serious emergency”). And in any
event, the Posse Comitatus Act expressly permits the use of
the military to execute the laws when permitted by an Act
of Congress,2 and §12406(3) is of course part of such an Act.3
   The Court finds the Posse Comitatus Act relevant largely
because the same phrase—“to execute the laws”—also ap-
pears in §12406(3). The Court’s reasoning appears to go as
follows. Under a position long taken by the Government,
the Posse Comitatus Act does not forbid the use of the mil-
itary for “protective functions.” This must mean that the
performance of such functions does not constitute the
——————
   2 The Act states: “Whoever, except in cases and under circumstances

expressly authorized by the Constitution or Act of Congress, willfully uses
any part of the Army, the Navy, the Marine Corps, the Air Force, or the
Space Force as a posse comitatus or otherwise to execute the laws shall
be fined under this title or imprisoned not more than two years, or both.”

 (emphasis added).
   3 I would not take for granted that the Posse Comitatus Act applies to

federalized National Guard units, another question that this Court has
never addressed. Indeed, the Act’s enumeration of other military com-
ponents—“the Army, the Navy, the Marine Corps, the Air Force, [and]
the Space Force”—makes the omission of the National Guard quite no-
table. If, as the Court states, the term “regular forces” in §12406 likely
means the military, Congress clearly views the military and federalized
National Guard units as distinct entities. Otherwise, §12406 would non-
sensically say that the President may call up the National Guard when
the National Guard is unable to execute the laws. It is therefore not
obvious that the Posse Comitatus Act would ever apply to federalized
National Guard units, as opposed to the regular military. As §12405
makes clear, some of the laws and regulations governing “members of
the Regular Army or Regular Air Force” are not applicable to the Na-
tional Guard “when called into Federal service.” 

.
                  Cite as: 

 (2025)            15

                      ALITO, J., dissenting

execution of the laws. Section 12406(3) allows the use of
federalized National Guard members “to execute the laws.”
Therefore, it follows that the National Guard may not be
used for protective functions.
   The Court’s reasoning rests on the presumption that a
phrase has the same meaning when it is used in closely re-
lated statutory provisions, but that presumption is not con-
clusive, and there are reasons to question its application
here. OLC’s interpretation of the Posse Comitatus Act is
based heavily on the history and purpose of that Act, not
the ordinary meaning of the phrase “execute the laws,”
which easily encompasses protective functions. See 1 Supp.
Op. OLC, at 344 (examining the “history,” “purpose,” and
“desig[n]” of the Posse Comitatus Act). Moreover, one of
OLC’s reasons for narrowly interpreting the Posse Comita-
tus Act’s reach was to avoid intrusion on the President’s in-
herent Article II powers and duties. See ibid. (noting the
“President’s constitutional duty to protect [federal] func-
tioning” and “inherent authority to use troops, if necessary,
to carry out this duty”). Interpreting the phrase “execute
the laws” in §12406 in accordance with the ordinary mean-
ing of its terms would not pose any similar problem.
   On the contrary, that interpretation would be consistent
with the way the phrase is used elsewhere. Under Article
II, §3 of the Constitution, the President must “take Care
that the Laws be faithfully executed,” and laws protecting
federal officers and property are not excepted. Nor do we
read the Insurrection Act, which authorizes the use of mili-
tia and armed forces to “enforce the laws,” as preventing the
President from ordering troops to serve protective func-
tions. 

. It is therefore entirely possible that
the phrase has different meanings in §12406 and the Posse
Comitatus Act, especially since what §12406 authorizes is
not the use of the regular military but the National Guard.
   We should not hastily dismiss that possibility because in-
terpreting §12406(3) in the way the Court suggests would
16                   TRUMP v. ILLINOIS

                      ALITO, J., dissenting

have very strange consequences that Congress is unlikely
to have intended. Under the Court’s interpretation, Na-
tional Guard members could arrest and process aliens who
are subject to deportation, but they would lack statutory
authorization to perform purely protective functions.
   Our country has traditionally been wary of using soldiers
as domestic police, but it has been comfortable with their
use for purely protective purposes. The Court’s interpreta-
tion of §12406(3) assumes that Congress meant for that pro-
vision to turn this approach on its head.
                         *     *     *
   In conclusion, the Court should have decided this appli-
cation based on the arguments the parties chose to present,
and on that basis should have granted a stay. Injecting an-
other issue into the matter was unwise, and suggesting
views on a host of important questions without adequate
briefing, consideration, or explanation is imprudent.
   Whatever one may think about the current administra-
tion’s enforcement of the immigration laws or the way ICE
has conducted its operations, the protection of federal offic-
ers from potentially lethal attacks should not be thwarted.
   I therefore respectfully dissent.
                  Cite as: 

 (2025)             1

                     GORSUCH, J., dissenting

SUPREME COURT OF THE UNITED STATES
                          _________________

                           No. 25A443
                          _________________


  DONALD J. TRUMP, PRESIDENT OF THE UNITED
       STATES, ET AL. v. ILLINOIS, ET AL.
                 ON APPLICATION FOR STAY
                      [December 23, 2025]

   JUSTICE GORSUCH, dissenting.
   This case touches on sensitive and gravely consequential
questions concerning what roles the National Guard and
U. S. military may play in domestic law enforcement. To be
sure, as the parties observe, Congress has supplied us with
some relevant statutory guidance in 

(3).
But, as my colleagues’ writings attest, that statute raises
as many questions as it answers.
   Take just some examples. Before calling up the National
Guard under §12406(3), must the President be unable to
execute the laws merely with federal civilian law enforce-
ment personnel—or must he be unable to do so even with
military troops? Is a Presidential declaration that he is un-
able with the regular forces to execute the law judicially re-
viewable—and, if so, to what extent and under what stand-
ard?     Does §12406(3) provide standalone authority
permitting the President to deploy the Guard, and how does
it interact with other statutes in the field, such as the Posse
Comitatus Act, 

, and the Insurrection Act,
10 U. S. C. §§251–255? What, if any, inherent Article II
power does the President have to deploy the Guard to pro-
tect federal personnel or property, and how might that in-
form the interpretation of §12406(3)? And if, as all parties
seem to assume, today’s Guard is the successor to the mili-
tia of the founding era, how far can this inherent Presiden-
tial authority extend before it intrudes on Congress’s
2                    TRUMP v. ILLINOIS

                    GORSUCH, J., dissenting

prerogative to decide when the militia may be used to exe-
cute the laws? See Art. I, §8, cl. 15. If all those questions
were not fraught enough, an even graver one lurks here too:
When, if ever, may the federal government deploy the pro-
fessional military for domestic law enforcement purposes
consistent with the Constitution? See, e.g., Art. IV, §4;
Amdt. 14, §5.
   In the present posture of this case, I am not comfortable
venturing an answer to any of those questions. This Court
has never decided a case about the meaning of §12406(3),
let alone explored its interaction with other statutes in the
field or the Constitution. Nor do we have much help on
many of these matters from the parties’ briefs before us, un-
derstandably given that this case comes to us in an inter-
locutory posture on a highly compressed schedule.
   Under these circumstances, caution seems to me key, and
I would decide this application narrowly, based only on
those few arguments the parties preserved and the eviden-
tiary record as it stands. See United States v. Sineneng-
Smith, 

 (2020). In their initial briefing
before this Court, the parties proceeded on the premise that
§12406(3) statutorily permits the President to call up and
deploy the National Guard when he is unable to execute
federal law with civilian federal law enforcement officials.
Proceeding on that same premise, I believe the declarations
federal law enforcement officials submitted below support
the grant of a stay for substantially the reasons given in
Parts I–A, B–1, C, and D of JUSTICE ALITO’s opinion. See
ante, at 2–11. But I would hazard no opinion beyond that,
leaving instead all the weighty questions outlined above for
another case where they are properly preserved and can re-
ceive the full airing they so clearly deserve.