Order Code RS22266
Updated December 26, 2006
The Use of Federal Troops for Disaster
Assistance: Legal Issues
Jennifer K. Elsea
Legislative Attorney
American Law Division
Summary
Hurricane Katrina raised questions concerning the President’s legal authority to
send active duty military forces into a disaster area and the permissible functions the
military can perform to protect life and property and maintain order. The Stafford Act
authorizes the use of the military for disaster relief operations at the request of the state
governor, but it does not authorize the use of the military to perform law enforcement
functions, which is ordinarily prohibited by the Posse Comitatus Act. However, the
President may invoke other authorities to use federal troops to aid in the execution of
the law, including the Insurrection Act, as amended and renamed by P.L. 109-364 (H.R.
5122/S. 2766). This report summarizes the possible constitutional and statutory
authorities and constraints relevant to the use of armed forces, including National Guard
units in federal service, to provide assistance to states when a natural disaster impedes
the operation of state and local police.
Recognizing the risk that a standing army could pose to individual civil liberties and
the sovereignty retained by the several states, but also cognizant of the need to provide
for the defense of the nation against foreign and domestic threats, the framers of the
Constitution incorporated a system of checks and balances to divide the control of the
military between the President and Congress and to share the control of the militia with
the states. This report summarizes the constitutional and statutory authorities and
limitations relevant to the employment of the armed forces to provide disaster relief and
law enforcement assistance.
Congress has the constitutional power to raise, support, organize and regulate the
armed forces, art. I, § 8, cls. 11-14. These clauses do not expressly limit Congress as to
how, when, or where it might employ the armed forces, although presumably such use
must be in furtherance of other constitutional powers. Congress is also empowered to
provide for calling forth the militia to execute federal law and to suppress insurrections,
§ 8, cl. 15, and to provide for organizing, arming, and disciplining the militia and to
govern them when they are employed in the service of the United States, § 8, cl. 16. Once
the army is raised or the militia called forth, the President serves as their Commander-in-

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Chief, art. II, § 2, cl. 1. And of course, the President is vested with the responsibility to
“take Care that the Laws be faithfully executed,” art. II, § 2, cl. 3. Congress has delegated
to the President the authority to use the armed forces to respond to a variety of domestic
crises, and Presidents have asserted some inherent authority to use the military even
without express statutory authorization.
Under the Constitution, states retain the primary responsibility and authority to
provide for civil order and the protection of their citizens’ lives and property. However,
the Constitution provides that the federal government is responsible for protecting the
states against invasion and insurrection, and, if the state legislature (or the governor, if the
legislature cannot be convened) requests it, protection against “domestic Violence,” art.
IV, § 4. States may not keep their own standing armies, art. I, § 10, cl. 3, but they retain
the authority to call forth their militias to suppress insurrections or quell civil
disturbances, subject to any restraints imposed by the Constitution or by Congress, in the
exercise of its constitutional powers. Congress has complete authority over federal lands,
military installations, and similar areas, art. I, § 8, cl. 17.
The Posse Comitatus Act
The Constitution does not explicitly bar the use of military forces in civilian
situations or in matters of law enforcement, but the United States has traditionally
refrained from employing troops to enforce the law except in cases of necessity. The
Posse Comitatus Act (PCA), 18 U.S.C. § 1385, punishes those who, “except in cases and
under circumstances expressly authorized by the Constitution or Act of Congress,
willfully use[] any part of the Army or the Air Force as a posse comitatus or otherwise to
execute the laws....”1 Questions arise most often in the context of assistance to civilian
police. At least in this context, the courts have held that, absent a recognized exception,
the PCA is violated (1) when civilian law enforcement officials make “direct active use”
of military investigators, (2) when the use of the military “pervades the activities” of the
civilian officials, or (3) when the military is used so as to subject citizens to the exercise
of military power that is “regulatory, prescriptive, or compulsory in nature.” The Act does
not apply to the Navy or Marines2 and does not prohibit activities conducted for a military
purpose (base security or enforcement of military discipline) that incidentally benefit
civilian law enforcement bodies. The Act does not apply to the National Guard unless it
is employed in federal service.
Statutory Exceptions. Congress has provided for a number of statutory
exceptions to the PCA by explicitly vesting law enforcement authority either directly in
a military branch (e.g, the Coast Guard) or indirectly by authorizing the President or
another government agency to call for assistance in enforcing certain laws.3
1 See CRS Report 95-964, The Posse Comitatus Act and Related Matters: The Use of the Military
to Execute Civilian Law
by Charles Doyle.
2 Department of Defense regulations effectively place them under similar constraints, and the
limitations on assistance to civilian law enforcement authorities apply to them, 10 U.S.C. § 375.
3 For a list of these authorities, see CRS Report 95-964 at ns. 63-64.

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Enforcement of the Laws to Restore Public Order (the Insurrection Act).
Congress has delegated authority to the President to call forth the military during an
insurrection or civil disturbance, 10 U.S.C. §§ 331-335. Section 331 authorizes the
President to use the military to suppress an insurrection at the request of a state
government, which is meant to fulfill the federal government’s responsibility to protect
states against “domestic violence” (although the term “insurrection” is arguably much
narrower than the phrase “domestic violence”). Section 332 delegates Congress’s power
under the Constitution, art. I, § 8, cl. 14, to the President, authorizing him to determine
that “unlawful obstructions, combinations, or assemblages, or rebellion against the
authority of the United States make it impracticable to enforce the laws of the United
States” and to use the armed forces as he considers necessary to enforce the law or to
suppress the rebellion. Section 333 permits the President to use the armed forces to
suppress any “insurrection, domestic violence, unlawful combination, or conspiracy” if
law enforcement is hindered within a state, and local law enforcement is unable to protect
individuals, or if the unlawful action “obstructs the execution of the laws of the United
States or impedes the course of justice under those laws.” This section was enacted to
implement the Fourteenth Amendment and does not require the request or even the
permission of the governor of the affected state.
The Insurrection Act has been used been used to send the armed forces to quell civil
disturbances a number of times during U.S. history, most recently during the 1992 Los
Angeles riots and during Hurricane Hugo in 1989, during which widespread looting was
reported in St. Croix, Virgin Islands. If the President decides to respond to such a
situation, generally upon the recommendation of the Attorney General and, if necessary,
the request of the governor, he must first issue a proclamation ordering the insurgents to
disperse within a limited time, 10 U.S.C. § 334.4 If the situation does not resolve itself,
the President may issue an executive order to send in troops.5
The 109th Congress included in the Defense Authorization bill for FY2007 (P.L. 109-
364) a provision that retitled chapter 15 of title 10 from “Insurrection” to “Enforcement
of the Laws to Restore Public Order,” and amended 10 U.S.C. § 333 explicitly to cover
instances of “domestic violence” where public order is disrupted due to a “natural
disaster, epidemic, or other serious public health emergency, terrorist attack or incident,
or other condition.” (Section 1076). Section 333, as amended, authorizes the President
to employ federal troops to “restore public order and enforce the laws of the United
States,” without a request from the governor or legislature of the state involved, in the
event he determines that local authorities are unable to maintain public order, where, as
before, either the enjoyment of equal protection of the laws is impeded or the execution
of federal law and related judicial process is obstructed. On exercising the authority, the
President is required to notify Congress as soon as practicable and every 14 days until
ordinary law enforcement is restored. The authority in section 333 remains unchanged,
except that the President’s recourse to “any other means” is eliminated, and the relevant
4 See, e.g., Proclamation No. 6427, 57 Fed. Reg. 19,359 (May 1, 1992) (citing California
governor’s notification and request related to rioting in Los Angeles, and also determining that
the “domestic violence and disorder are also obstructing the execution of the laws of the United
States”); Proclamation No. 6023, 54 Fed. Reg. 39,151 (Sep. 20, 1989)(Virgin Islands).
5 See, e.g., Exec. Order No. 12804, 57 Fed. Reg. 19361 (May 1, 1992); Exec. Order No. 12690,
54 Fed. Reg. 39153 (Sep. 20, 1989).

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state is to be deemed to have denied constitutional equal protection any time the authority
is exercised outside of the newly described disaster scenario, rather than when “any part
or class of [the state’s] people is deprived of a right, privilege, immunity, or protection
named in the Constitution and secured by law,” although this remains one of the
alternative prerequisites for invoking the authority even under disaster conditions.
Congress also provided authority to the President, in exercising the provision above and
irrespective of whether the Stafford Act is invoked, to direct the Secretary of Defense to
provide supplies, services, and equipment necessary for the immediate preservation of life
and property, until state authorities or other federal agencies are able to provide them, so
long as military preparedness or operations are not thereby impeded.
Military Support for Law Enforcement Agencies. Congress has also
authorized the armed forces to share information and equipment with civilian law
enforcement agencies, 10 U.S.C. §§ 371-382, although prohibiting the use of armed
forces personnel to make arrests or conduct searches and seizures.
Inherent Emergency Power. Department of Defense (DOD) regulations assert
another exception that does not rest on statutory authority, but is available in very limited
circumstances and covers
Actions that are taken under the inherent right of the U.S. Government . . . to ensure
the preservation of public order and to carry out governmental operations within its
territorial limits, or otherwise in accordance with applicable law, by force, if
necessary.6
The emergency power, according to DOD directives, is available to protect federal
property and functions, and to authorize
prompt and vigorous Federal action, including use of military forces, to prevent loss
of life or wanton destruction of property and to restore governmental functioning and
public order when sudden and unexpected civil disturbances, disaster, or calamities
seriously endanger life and property and disrupt normal governmental functions to
such an extent that duly constituted local authorities are unable to control the
situation.7
Ordinarily, the implementation of such operations must be authorized by executive order,
but DOD officials and military commanders may take emergency action without prior
authorization in cases where
sudden and unexpected civil disturbances (including civil disturbances incident to
earthquake, fire, flood, or other such calamity endangering life) occur, if duly
constituted local authorities are unable to control the situation and circumstances
preclude obtaining prior authorization by the President.8
6 DOD Cooperation with Civilian Law Enforcement Officials, DOD Dir. 5525.5 (Encl. 4) §
E4.1.2.3 (1989).
7 Id.
8 Military Assistance for Civil Disturbances, DOD Dir. 3025.12 § 4.2.2. (1994).

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The Stafford Act
The Robert T. Stafford Disaster Relief and Emergency Assistance Act (the Stafford
Act, 42 U.S.C. §§ 5121, et seq.) authorizes the President to make a wide range of federal
aid available to states that are stricken by a natural or man-made disaster.9 It provides
statutory authority for employing the U.S. armed forces for domestic disaster relief.
Permitted operations include debris removal and road clearance, search and rescue,
emergency medical care and shelter, provision of food, water, and other essential needs,
dissemination of public information and assistance regarding health and safety measures,
and the provision of technical advice to state and local governments on disaster
management and control. The authority does not constitute an exception to the PCA. In
the event of a disaster that results in the wide-scale deterioration of civil law and order,
the authority to employ active duty troops to perform law enforcement functions must be
found elsewhere. The Stafford Act does not authorize the use of federal military forces
to maintain law and order. Federal forces would have no authority, for example, to act
as traffic controllers or provide security for facilities used in the relief efforts, unless such
activities serve a valid military purpose. Patrolling in civilian neighborhoods for the
purpose of providing security from looting and other activities, would not be permissible,
although patrolling for humanitarian relief missions, such as rescue operations and food
delivery (which may have the incidental benefit of deterring crime) would not violate the
PCA. Military resources may be employed in the following situations.
Essential Assistance (10-Day Authority). Upon the request of the governor,
the President may task the Department of Defense to provide any emergency work the
President deems essential for the preservation of life and property in the immediate
aftermath of an incident that may ultimately qualify for assistance under a declaration.
Such assistance is available for up to ten days prior to a presidential declaration of an
emergency or a major disaster, 42 U.S.C. § 5170b(c). Emergency work can include the
clearance and removal of debris and wreckage and the restoration of essential public
facilities and services, 42 U.S.C. § 5170(c)(6)(B). The provision is designed for instances
where communications problems impede the ability to meet the prerequisites for declaring
an emergency or major disaster or the ability to coordinate the work through FEMA.
Emergency. Unless the President determines that a disaster implicates
preeminently federal interests, the declaration of an emergency under the Stafford Act
requires that the governor of the affected state first make a determination that the situation
is of such severity and magnitude that the state is unable to respond effectively without
federal assistance, which determination must include a detailed definition of the type and
amount of federal aid required, 42 U.S.C. § 5191. The governor must also implement the
state’s emergency response plan, for example, by activating the state’s National Guard
units under state control (in which case the PCA does not apply to them), and provide
information regarding the resources that have been committed.
Major Disaster. The prerequisites for a major disaster declaration are similar to
those for an emergency, 42 U.S.C. § 5170. The governor must first execute the state’s
emergency plan and make a determination that state capabilities are insufficient to deal
9 For an overview of the Stafford Act, see CRS Report RL33053, Federal Stafford Act Disaster
Assistance: Presidential Declarations, Eligible Activities, and Funding
, by Keith Bea.

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with the circumstances. However, the governor need not specify which forms of
assistance are needed. The governor must provide information regarding the resources
that have been committed and certify that the state will comply with cost sharing
provisions under the Stafford Act. There is no provision for the declaration of a major
disaster without the governor’s request. If the governor activates Guard units and keeps
them under state control, those units are not restricted by the PCA. If the state’s National
Guard units are called into federal service to respond to an emergency or a major disaster,
their role is restricted to the disaster relief operations authorized under the Stafford Act.
Immediate Response Authority
DOD doctrine allows commanders to provide resources and assistance to civil
authorities without or prior to a declaration under the Stafford Act when a disaster
overwhelms the capabilities of local authorities and necessitates immediate action “to
prevent human suffering, save lives, or mitigate great property damage.”10 Immediate
response actions can include the types of activities authorized under the Stafford Act,
including, at the request of civil authorities, rescue, evacuation, and emergency medical
treatment, restoration of essential public services, debris removal, controlling
contaminated areas, safeguarding and distributing food and essential supplies, and
supplying interim emergency communications.11 The immediate response authority may
also include law enforcement activities ordinarily prohibited by the PCA. The controlling
directive does not require a request from state or local officials, but states that
DoD Components shall not perform any function of civil government unless
absolutely necessary on a temporary basis under conditions of Immediate Response.
Any commander who is directed, or undertakes, to perform such functions shall
facilitate the reestablishment of civil responsibility at the earliest time possible.12
The immediate response authority is not provided for in any statute, but is said to
have deep historical roots.13 The 1906 San Francisco earthquake is a noted example. The
commanding general of the Pacific Division, on his own initiative, deployed troops to
assist civil authorities to stop looting, protect federal buildings, and to assist firefighters.14
Legislative Action
In addition to amending the Insurrection Act, the 109th Congress amended10 U.S.C.
§ 12304(c) to remove the restriction on reserve call-up authority for disaster assistance.
Concern on the part of some state officials that these changes will induce presidents to
federalize National Guard troops in response to natural disasters against the will of the
governor may lead to calls for the 110th Congress to revisit the issue.
10 U.S. Dep’t of Defense, Military Support to Civil Authorities, DOD Dir. 3025.1 § 4.5 (1993).
11 Id. § 4.5.1.
12 Id. § 4.4.10.
13 See Jim Winthorp, The Oklahoma City Bombing: Immediate Response Authority and Other
Military Assistance to Civil Authority (MAC)
, ARMY LAW. 3 (July, 1997).
14 Id. at 5.