War and Treaty Powers
The issue: How have the war and treaty powers in the Constitution been interpreted?

War Powers of President

The Constitution divides war powers between the Congress and the President.  This division was intended by the framers to ensure that wars would not be entered into easily: it takes two keys, not one, to start the engine of war. 

The Constitution's division of powers leaves the President with some exclusive powers as Commander-in-Chief (such as decisions on the field of battle), Congress with certain other exclusive powers (such as the ability to declare war and appropriate dollars to support the war effort), and a sort of "twilight zone" of concurrent powers.  In the zone of concurrent powers, the Congress might effectively limit presidential power, but in the absence of express congressional limitations the President is free to act.  Although on paper it might appear that the powers of Congress with respect to war are more dominant, the reality is that Presidential power has been more important--in part due to the modern need for quick responses to foreign threats and in part due to the many-headed nature of Congress.

The Supreme Court has had relatively little to say about the Constitution's war powers.  Many interesting legal questions--such as the constitutionality of the "police action" in Korea or the "undeclared war" in Viet Nam--were never decided by the Court.  (Although the Supreme Court had three opportunities to decide the constitutionality of the war in Viet Nam, it passed on each one.)

During the Civil War, the Court issued two significant opinions interpreting the war powers.  In the Prize Cases (1863), the Court on a 5 to 4 vote upheld President Lincoln's order blockading southern ports--even though the order was issued prior to a formal declaration of war on the Rebel states by Congress.  The Court found Lincoln's action authorized by a 1795 Act allowing the President to call out troops to suppress an insurrection.  The dissenters argued the President's action were unconstitutional, as a blockade is quite different that an action merely directed at those participating in an insurrection.  Three years later, in Ex Parte Milligan, the Court found unconstitutional Lincoln's order authorizing trial by a military tribunal of Lambdin P. Milligan, an Indiana lawyer accused of stirring up support for the Confederacy.  The Court ruled that civilians must be tried in civilian courts, even during time of war, so long at least as the civilian courts are open and operating.  The Court also found the President lacked authority to declare martial law in Indiana.  Four concurring justices argued that even though the President did not have the power to order a military trial of Milligan in the absence of congressional action, the power to authorize use of military tribunals did reside in Congress under its war power.

In 1942, in Ex Parte Quirin, the Court considered the constitutionality of an order of President Roosevelt authorizing trial by military commission of eight German Nazi saboteurs arrested after entering the United States.  The eight had planned to blow up munitions factories and military installations in the United States.  The Court, voting 8 to 0, upheld the legality of trying the Germans (who the Court found to be unlawful combatants) in a military tribunal without the usual safeguards of the 5th and 6th Amendments.  The Court found the authorization of trial by tribunal supported by legislation enacted by Congress, and noted that it need not decide whether a presidential order of trial by commission would be constitutional in the absence of congressional action. 

Two alleged Nazi saboteurs, Herbert Haupt (L) and John Dasch (R), at their trial by military commission at the Department of Justice in 1942.
LINK: Read an FBI account of the Nazi saboteur episode

In 2006, the Supreme Court ruled in Hamdan v Rumsfield that President Bush exceeded his powers under the Constitution when he ordered that post 9-11 detainees held at Guantanamo, Cuba be put on trial before military commissions.  The Court, 5 to 3, rejected the Administration's claims that the President either had the inherent power to order such trials or that the trials were authorized by Congressional action through its Authorization for the Use of Military Force (AUMF) Resolution following the terrorist attacks in 2001.  Writing for the Court, Justice Stevens said that trials must comply with the Uniform Code of Military Justice (the code governing courts martial) and the Geneva Convention.   The three dissenters concluded that Congress had "constitutionally eliminated jurisdiction over this case," and therefore that Hamdan's case should be dismissed.

War Powers of Congress

In Hamilton v Kentucky Distilleries (1919), the Court considered the constitutionality of a federal law, enacted under the war power of Congress, prohibiting the sale and distribution of distilled spirits.  Congress said the Act was necessary "for the purpose of conserving the man power of the Nation, and to increase efficiency in the production of arms, munitions, ships, food, and clothing for the army and navy."  Justice Brandeis, writing for the Court, found the restriction to be within the war powers of Congress and that the Act was not a taking requiring just compensation.  The Court said that although at some time after the cessation of hostilities the restriction must come to an end, it would be reluctant to conclude that the war power was no longer effective so long as some troops remained abroad and some other wartime measures remained in effect.

Louisiana-born Yaser Esam Hamdi

On June 28, 2004, the Court ruled in two important cases challenging actions of the Bush Administration taken subsequent to the 9-11 acts of terrorism.  In Hamdi v Rumsfeld, the Court ruled that Congress, in its 2001 Authorization for the Use of Military Force, had given the President the power to declare an American citizen an "enemy combatant" and deny him a trial in federal court.  Justice O'Connor, writing for the majority did, however, indicate that such persons cannot be held indefinitely and were entitled to contest the determination of their status with the assistance of counsel. Justice Scalia, somewhat surprisingly dissented, arguing that the Constitution entitled Hamdi to a criminal trial.  He concluded:

"The Founders well understood the difficult tradeoff between safety and freedom. "Safety from external danger," Hamilton declared, "is the most powerful director of national conduct. Even the ardent love of liberty will, after a time, give way to its dictates. The violent destruction of life and property incident to war; the continual effort and alarm attendant on a state of continual danger, will compel nations the most attached to liberty, to resort for repose and security to institutions which have a tendency to destroy their civil and political rights. To be more safe, they, at length, become willing to run the risk of being less free." The Federalist No. 8, p. 33.

The Founders warned us about the risk, and equipped us with a Constitution designed to deal with it.

Many think it not only inevitable but entirely proper that liberty give way to security in times of national crisis-that, at the extremes of military exigency, inter arma silent leges. Whatever the general merits of the view that war silences law or modulates its voice, that view has no place in the interpretation and application of a Constitution designed precisely to confront war and, in a manner that accords with democratic principles, to accommodate it. Because the Court has proceeded to meet the current emergency in a manner the Constitution does not envision, I respectfully dissent.

The Court in Hamdi did conclude, however, that under due process principles that citizens designated as enemy combatants were entitled to  a written statement of the basis for that declaration, as well as a right to challenge it before a neutral decision-maker in a timely manner.  In the other 9-11 case, Rasul v Bush, the Court ruled 6 to 3 that aliens detained in Guatanamo, Cuba had the right to challenge their detention in American courts, in part because the United States had exclusive jurisdiction and control over the base in Cuba.

In 2006, the Supreme Court revisited the question of constitutionally-required process for detainees at Guantanamo in the case of Hamdan vs Rumsfield.  Hamdan conceded that the government had the right to court-martial him, but argued that trial by military commission in his case was neither authorized by statute or constitutional.  The Supreme Court agreed, holding that trials by military commission were authorized by Congress only for (1) offenses that occurred in a theater of war, (2) during a period of war, and (3) were offenses that involved an illegitimate form of warfare.  In the case of Hamdan, accused of conspiracy "to commit an offense triable by military commission," and who was alleged to have been a driver for Osama Bin Laden and arranged for transportation of weapons to Al Qaeda before U. S. action against Al Qaeda, the Court found none of the three necessary conditions met.

Power to Suspend the Writ of Habeas Corpus

In 2008, the Supreme Court in Boumediene et al. v Bush considered whether aliens designated as "enemy combatants" and held at a U. S. base at Guantanamo Bay, Cuba had the right to seek a writ of habeas corpus, despite an act of Congress that attempted to suspend that right. The Supreme Court, voting 5 to 4, concluded that they did.  Writing for the Court, Justice Kennedy found that the constitutional privilege of seeking a writ extended to aliens detained on territory over which the United States is the de facto (if not de jure) sovereign and that the review process established for Guantanamo detainees was not an adequate substitute for habeas corpus review and therefore violated Article I, Section 9.

Treaty Power

Missouri v Holland (1920)
Medelln v Texas (2008)

The case of Missouri v Holland (1920) presented the Court with an opportunity to define the reach of the treaty power.  Missouri challenged the federal government's regulation of the hunting of migratory birds, including its setting of seasons, hunting methods, and limits.  The regulations were adopted under the Migratory Bird Treaty Act, implementing a treating signed by the United States and Great Britain (for Canada).  The Court upheld the regulations, even though they were not supported by specific Article I powers of Congress, as a reasonable implication of the President's Article II power to "make treaties."  The Court cautioned, however, that the treaty-implementing power could not be used as an excuse for regulating activities that were not "a proper subject of regulation."

In Medelln v Texas (2008), the Court considered whether President Bush had the power to order Texas courts to reopen a criminal case after the International Court of Justice issued an order to that effect, finding that Texas officials had (inconsistent with the Vienna Convention) failed to notify Medelln, a Mexican national, that he had the right to contact the Mexican consulate after his arrest.  The Court held that the president lacked the constitutional authority to turn a non-self-executing treaty into a treaty that effectively bound state officials.


Lambdin P. Milligan

Ex Parte Milligan (1866)
Ex Parte Quirin (1942)
Hamdi v Rumsfeld (2004)
Hamilton v Kentucky Distilleries (1919)
Hamdan v Rumsfield (2006)
Boumediene v Bush (2008)


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; 

To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions; 

To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress....


The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it.


The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States....

He shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur....

Migratory Bird Treaty Act


1. What sort of actions might fall within the "zone of concurrent power" in which either the Congress or President might constitutionally act, so long as Congress hasn't expressly limited the power of the President?
2.  Does the modern world require that the President have war power authority never envisioned by the framers?  For example, can Congress respond sufficiently quickly to hijackings, terrorist bombings at overseas facilities, and other threats to American citizens?

3.  A relatively rare effort by Congress to limit the President's power in the area of overseas military actions came in the War Powers Act of 1973, which required the President to report on troop commitments into hostile situations within 48 hours and required withdrawl of troops within 60 to 90 days unless the deployment were authorized by Congress.  What is likely to happen if a President ignores the Act's provisions? What if the President contends the acts provisions have not been triggered?  Would such a case, if litigated, present a "political question" that a court should not decide?  Could a court order American troops to come home?

4.  Under what circumstances is it constitutional to try persons before military tribunals?  Was it constitutional to try southern-sympathizers involved in John Wilkes Booth's plot on President Lincoln and other high government officials?  Does it matter whether the plotters had connections with the Confederate Secret Service?  Three hundred Dakota warriors were sentenced to death in 1862 by a military tribunal for their role in an uprising against Minnesota settlers--was that constitutional?  Would it be constitutional to try by military tribunal an American citizen found to have participated in the World Trade Center attack?  A Canadian citizen?

5.  Under what circumstances might a President declare martial law? (The Court, in 1946 (the year may be important!), found unconstitutional President Roosevelt's declaration of martial law in the Hawaii Territory following the attack on Pearl Harbor.)

6.  Could the President sign a treaty with Canada relating to deer hunting (some deer, of course, cross the border) and then precede to enforce implementing legislation that set deer hunting seasons and limits across the country?

7.  Does the Constitution give the President the power to restrict travel by American citizens to places such as Cuba?

8.  Should Hamdi (and other citizens declared "enemy combatants" after 9-11 be entitled to a criminal trial, or should some lesser fact-finding process suffice?  Did the Court in Hamdi strike a proper balance, using the Matthews balancing test, between the security concerns of the government and the liberty interests of Hamdi?
9.  Do you consider it likely or unlikely that significant numbers of declared enemy combatants after 9-11 were in fact not enemy combatants at all, but rather persons erroneously deprived of their liberty?
10.  In Hamdan v Rumsfield, the Supreme Court concludes that Congress's  post-9/11 AUMF did not authorize the President to establish military commissions to try detainees held on charges of conspiracy to commit terrrorism.  Does Hamdan suggest also that the President lacked authority to establish the NSA surveillance program, described below? 

The N. S. A. Controversy: Does the President have the power to wiretap the phone calls of Americans without a court order?

It was revealed in 2006 that the President had authorized, following the 2001 attacks in New York,  the National Security Agency to institute a program to intercept phone calls and e-mails--without warrants-- sent by Americans to persons overseas.  Critics of the program, and most constitutional scholars who have weighed in on the subject, call the program illegal.

In testimony before a Senate Committee, A. G. Gonzales argued that the surveillance program was permitted under a 2001 congressional resolution giving the President the power "to use all necessary and appropriate force" to combat Al Qaeda.  Moreover, Gonzales said, the President, as commander-in chief, had the inherent authority (authority even in the absence of congressional action) to authorize the NSA spying program .  Gonzales faced tough questioning from senators who pointed to a 1978 law (the Foreign Intelligence Surveillance Act, or FISA) that clearly prohibited intercepting the phone calls of American citizens without a warrant from a court.  Generally it is assumed that in the case of a potential conflict, the statute with the more specific language governs.  In this case, critics argued, the specific language prohibiting surveillance without a warrant in FISA clearly should trump the vague language of the 2001 resolution, which addresses use of "force," not wiretapping--and if a later act amends an earlier one, it should say so expressly.   Critics also suggested that the President's argument that he had the inherent power as commander-in-chief to authorize the program was too broad to be plausible. Wouldn't the argument , they claimed, also allow the President to seize and torture American citizens, if he thought such a step was necessary to combat terrorism?

Consider the Supreme Court's decision in the case of  Youngstown Sheet & Tube Co. v Sawyer (1952)
and Hamdi v RumsfieldIs the President's surveillance program constitutional?

Read More About Two Famous Cases Involving Military Tribunals 

Dakota Conflict
Trials (1862)

Lincoln Assassination
Trial (1865)
 Exploring Constitutional Conflicts Homepage