https://crsreports.congress.gov
Updated December 21, 2021
Defense Primer: Congress’s Constitutional Authority with
Regard to the Armed Forces
Article I, Section 8, Clauses 11-14
The Congress shall have power *** ;
To declare War, grant Letters of Marque and Reprisal, and
make Rules concerning Captures on Land and Water.
To raise and support Armies, but no Appropriation of
Money to that Use shall be for a longer Term than two
Years.
To provide and maintain a Navy.
To make Rules for the Government and Regulation of the
land and naval Forces.
The War Powers
In Lichter v. United States, 334 U.S. 742 (1948), the
Supreme Court discusses the “war powers” of Congress as
the sum of many interconnected authorities found in the
Constitution. Addressing the constitutionality of the
Renegotiation Act, an act allowing the government to
renegotiate contracts related to war supplies during WWII,
the Court declared that
In view of this power ‘To raise and support Armies,
... and the power granted in the same Article of the
Constitution ‘to make all Laws which shall be
necessary and proper for carrying into Execution
the foregoing Powers,’ ... the only question
remaining is whether the Renegotiation Act was a
law ‘necessary and proper for carrying into
Execution’ the war powers of Congress and
especially its power to support armies.
In a footnote, the Court listed the Preamble, the Necessary
and Proper Clause, the provisions authorizing Congress to
lay taxes and provide for the common defense, to declare
war, and to provide and maintain a navy, together with the
clause designating the President as Commander-in-Chief of
the Army and Navy, as being “among the many other
provisions implementing the Congress and the President
with powers to meet the varied demands of war.... ”
The power “To declare War” has long been construed to
mean not only that Congress can formally take the nation
into war, but also that it can authorize the use of the Armed
Forces for military expeditions that may not amount to war.
While a restrictive interpretation of the power “To declare
War” is possible, for example, by viewing the Framers’ use
of the verb “to declare” rather than “to make” as an
indication of an intent to limit Congress’s ability to affect
the course of a war once it is validly commenced,
Congress’s other powers over the use of the military would
likely fill any resulting void. In practice, courts have not
sought to delineate the boundaries of each clause relating to
war powers or identify gaps between them to find specific
powers that are denied to Congress.
The Supreme Court has suggested, however, that Congress
might overstep its bounds into presidential territory if it
were to interfere with the conduct of military operations.
Debates relating to legislation regarded by some as
interfering with the President’s Commander-in-Chief
authority are frequently framed in terms of legislative
meddling in military operations, but the line between
regulating the Armed Forces and directing campaigns has
proved elusive.
Congress has also used its authority to provide for the
organization and regulation of the Armed Forces to
determine how military personnel are to be organized and
employed. For example, early statutes prescribed in fairly
precise terms how military units were to be formed and
commanded.
Examples of Legislation
The Uniform Code of Military Justice
The Uniform Code of Military Justice (UCMJ) is an
exercise of Congress’s power to raise and support armies
(Art. I, § 8, cl. 12); provide and maintain a Navy (Art. I,
§ 8, cl.13); and to make rules for organizing and
disciplining their members (Art. I, § 8, cl. 14). Under this
authority, Congress enacted the UCMJ (Chapter 47 of Title
10, U.S. Code), which is the code of military criminal laws
applicable to all U.S. military members worldwide.
The President implements the UCMJ through the Manual
for Courts-Martial (MCM), which was initially prescribed
by Executive Order 12473 (April 13, 1984). The MCM
contains the Rules for Courts-Martial (RCM), the Military
