Common Interpretation

Treason Clause


Treason is a unique offense in our constitutional order—the only crime expressly defined by the Constitution, and applying only to Americans who have betrayed the allegiance they are presumed to owe the United States. While the Constitution’s Framers shared the centuries-old view that all citizens owed a duty of loyalty to their home nation, they included the Treason Clause not so much to underscore the seriousness of such a betrayal, but to guard against the historic use of treason prosecutions by repressive governments to silence otherwise legitimate political opposition. Debate surrounding the Clause at the Constitutional Convention thus focused on ways to narrowly define the offense, and to protect against false or flimsy prosecutions.   

The Constitution specifically identifies what constitutes treason against the United States and, importantly, limits the offense of treason to only two types of conduct: (1) “levying war” against the United States; or (2) “adhering to [the] enemies [of the United States], giving them aid and comfort.” Although there have not been many treason prosecutions in American history—indeed, only one person has been indicted for treason since 1954—the Supreme Court has had occasion to further define what each type of treason entails.

The offense of “levying war” against the United States was interpreted narrowly in Ex parte Bollman & Swarthout (1807), a case stemming from the infamous alleged plot led by former Vice President Aaron Burr to overthrow the American government in New Orleans. The Supreme Court dismissed charges of treason that had been brought against two of Burr’s associates—Bollman and Swarthout—on the grounds that their alleged conduct did not constitute levying war against the United States within the meaning of the Treason Clause. It was not enough, Chief Justice John Marshall’s opinion emphasized, merely to conspire “to subvert by force the government of our country” by recruiting troops, procuring maps, and drawing up plans. Conspiring to levy war was distinct from actually levying war. Rather, a person could be convicted of treason for levying war only if there was an “actual assemblage of men for the purpose of executing a treasonable design.” In so holding, the Court sharply confined the scope of the offense of treason by levying war against the United States. 

The Court construed the other treason offense authorized by the Constitution similarly narrowly in Cramer v. United States (1945). That case involved another infamous incident in American history: the Nazi Saboteur Affair. Cramer was prosecuted for treason for allegedly helping German soldiers who had surreptitiously infiltrated American soil during World War II. In reviewing Cramer’s treason conviction, the Court explained that a person could be convicted of treason only if he or she adhered to an enemy and gave that enemy “aid and comfort.” As the Court explained: “A citizen intellectually or emotionally may favor the enemy and harbor sympathies or convictions disloyal to this country’s policy or interest, but, so long as he commits no act of aid and comfort to the enemy, there is no treason. On the other hand, a citizen may take actions which do aid and comfort the enemy—making a speech critical of the government or opposing its measures, profiteering, striking in defense plants or essential work, and the hundred other things which impair our cohesion and diminish our strength—but if there is no adherence to the enemy in this, if there is no intent to betray, there is no treason.” In other words, the Constitution requires both concrete action and an intent to betray the nation before a citizen can be convicted of treason; expressing traitorous thoughts or intentions alone does not suffice.

To further guard against the prospect that the government could use false or passion-driven accusations of treason to undermine political opponents, the Treason Clause provides that the offense may only be proven by “open confession in court,” or on “the testimony of two witnesses to the same overt act.” The “overt act” requirement was designed both to limit the kind of substantive behavior treason could punish—only conduct, not mere expression—and to ensure that the conduct itself demonstrated a defendant’s intention to betray the United States. Believing that no witness could meaningfully testify to a defendant’s internal state of mind, the Cramer Court made clear that the defendant’s disloyal intent must be evident from the witnessed acts themselves; the government would have to prove that each overt act alleged “actually gave aid and comfort to the enemy.” The two-witness requirement was likewise geared to raising the bar to prosecution, applying “at least to all acts of the defendant which are used to draw incriminating inferences that aid and comfort have been given.” While there was no dispute in Cramer’s case that he had met with a man who turned out to be a German soldier in the United States, the Court concluded that these facts alone failed to establish Cramer had actually given that enemy soldier aid and comfort. The Court accordingly reversed Cramer’s treason conviction.

The Constitution also narrowed the scope of punishment for treason as compared to English common law. The final clause of this Section establishes that, while Congress has the general power to establish the penalties for committing treason, Congress may not “work corruption of blood, or forfeiture except during the life of the person” convicted of treason. “Corruption of blood” is a reference to English common law, which prohibited family members from—among other things—receiving or inheriting property from a person convicted of treason. Under the Constitution, that punishment may not extend beyond the life of the person convicted of treason.

Matters of Debate

Does the Treason Clause Still Matter? (Yes.)


Treason prosecutions have essentially disappeared. Although treason was never a popular charge for federal prosecutors, treason prosecutions attended nearly every armed conflict in American history up to and including the Second World War. Since 1954, however, only one person has been charged with treason against the United States. And that single instance was relatively unusual: in 2006, a federal grand jury indicted Adam Gadahn for treason based on his participation in several al-Qaeda propaganda videos. Gadahn was not in custody at the time of his indictment, and he was later killed in a 2015 drone strike in Pakistan before he could stand trial in the United States.

The traditional explanation for why treason charges have vanished is that the Supreme Court in Cramer v. United States (1945) made treason so difficult to prove that it was no longer a realistic option for federal prosecutors. But that conventional wisdom is wrong. The Court in Cramer did make treason more difficult to prove than it otherwise could have, but it did not raise the bar so high that treason charges were no longer plausible. Indeed, the federal government pursued nearly a dozen treason prosecutions after the Court decided Cramer—and secured convictions in nearly all of those cases. As of 1954, there was little reason to believe that treason charges would fall into complete disuse.

A better explanation for the disappearance of treason prosecutions comes from another aspect of the Cramer decision. The government in Cramer argued that the Treason Clause should be interpreted leniently so that treason charges could be readily deployed during times of war. The Court dismissed the government’s concern, observing that “the treason offense is not the only nor can it well serve as the principal legal weapon to vindicate our national cohesion and security.” The Court further emphasized that “the power of Congress is in no way limited to enact prohibitions of specified acts thought detrimental to our wartime safety.” Critically, the Court indicated that federal prosecutors could pursue non-treason charges—offenses such as violating the Espionage Act or the Trading with the Enemy Act—without needing to satisfy the procedural requirements of the Treason Clause.

Another Perspective

This essay is part of a discussion about the Treason Clause with Deborah Pearlstein, Associate Professor of Law, Benjamin N. Cardozo School of Law, Yeshiva University. Read the full discussion here.

This understanding was confirmed a few years later during the prosecution of Julius and Ethel Rosenberg for disclosing atomic secrets to the Soviet Union. The Rosenbergs were charged with conspiracy to commit espionage, not treason. But prosecutors and even the trial judge often conflated the charges, referring to the Rosenbergs as “traitors” and having committed “treason.” The Rosenbergs claimed that their convictions had violated the Treason Clause, because they were effectively convicted of treason but without the attendant constitutional safeguards. The United States Court of Appeals for the Second Circuit rejected the Rosenbergs’ argument in 1952, and the Supreme Court declined to intervene the following year. 

By 1954, therefore, Rosenberg and Cramer had firmly established that prosecutors could bring non-treason charges without the procedural safeguards provided by the Treason Clause, even if the conduct at issue could plausibly be considered treasonous. At the same time, Congress passed several new national security laws, including the Internal Security Act of 1950 and the Communist Control Act of 1954. As the menu of federal crimes expanded, prosecutors had less and less reason to resort to treason charges. Why bother with the two-witness rule or the overt-act requirement when a variety of alternative (and substitute) offenses exist?

Because treason prosecutions have effectively disappeared, one might wonder about the continued relevance of the Treason Clause. But the Clause should not be relegated to the dustbin of history for at least two reasons. First and foremost, as the indictment against Adam Gadahn demonstrated, treason is not yet completely extinct. And because the Court in Cramer did not in fact make treason impossible to prove, there remains the possibility that treason charges could one day increase in relative frequency. If that does happen, the Treason Clause sets forth important requirements on how such charges must be proven. 

Second, while the specific protections set forth in the Treason Clause may be limited to treason prosecutions, the principles underlying the Clause are not. Indeed, they should serve as important reminders about national security cases more generally. The Framers correctly believed there was a crucial distinction between traitorous actions and treasonous thought. Departing from English common law, which at the time recognized constructive treason, the Constitution required some sort of action before a person could be convicted of treason. That line between conduct and conscience dovetails with First Amendment values, and is one that should be respected beyond the narrow confines of treason. In addition, the Framers recognized that national security offenses are more likely to inflame public passions, and therefore deserve heightened procedural protections. This insight also extends beyond treason cases, and is one Congress, federal courts, and the public would do well to remember.

Matters of Debate

Treason by Any Other Name


The Constitution uses the word “war” in only two places: in Article I, most famously in allocating to Congress the power to “declare war,” and again here in Article III, giving the courts the power to hear cases requiring them to determine whether an individual is guilty of “levying war” against the United States. The Treason Clause is in this sense among the stronger pieces of textual evidence that the courts were to have as much a role in evaluating the existence of certain individual threats to national security as they would in adjudicating any other kind of crime.

Indeed, particularly since the attacks of September 11, the federal courts have faced dozens upon dozens of cases involving accusations that individuals have aided our enemies—individuals charged not with treason, but with providing “material support” to a terrorist or a terrorist group. Yet while the Treason Clause includes special rules of evidence to help guard against the danger that otherwise peaceful opponents of our government would face false accusations of supporting our enemies, neither the material support statute, nor other comparable federal offenses, contain any such safeguards. Is it really consistent with the Treason Clause for there to be such a ready way to avoid its protections? For government to be able to achieve the same ends—prosecution for aiding the enemy—without having to encounter any of the hurdles designed to guard against the abuses of such a charge that so concerned the Framers?

While the Cramer Court recognized Congress’ broad power to criminalize a wide range of offenses harmful to the United States, the Court was also careful to underscore the reality that even this power had its limits: “Of course we do not intimate that Congress could dispense with the two-witness rule merely by giving the same offense another name.” As one appeals court facing a terrorism prosecution arising out of the first World Trade Center bombing thus acknowledged: “The question whether a defendant who engaged in subversive conduct might be tried for a crime involving all the elements of treason, but under a different name and without the constitutional protection of the Treason Clause, . . . remains open.”

Another Perspective

This essay is part of a discussion about the Treason Clause with Paul T. Crane, Assistant Professor of Law, University of Richmond School of Law. Read the full discussion here.

Lower courts have for the most part been able to avoid answering the question directly by concluding that other crimes, however similar, do not contain all of the same elements required to prove treason itself. Unlike treason, the crime of material support, for example, carries no requirement that defendants have breached an allegiance owed to the United States; citizens and non-citizens alike can be charged with the offense. At the same time, there is at least some reason to worry that material support prosecutions of Americans and American organizations could involve forms of expressive activity—translating enemy statements into English, or producing training material on international law that an enemy organization could use to peacefully resolve disputes—that the Framers would have expected to be prosecuted, if at all, only under heightened procedural protection. And while the label “traitor” may still today be a uniquely powerful public condemnation, those convicted of providing material support to any one of the five dozen organizations the United States currently lists as foreign terrorists bear substantial penalties of their own.

The Treason Clause, much like the Constitution’s first ten amendments, is principally designed to protect core individual rights—most especially freedoms of expression and dissent. As Justice Jackson explained for the Cramer Court: “[T]he basic law of treason in this country was framed by men who, as we have seen, were taught by experience and by history to fear abuse of the treason charge almost as much as they feared treason itself.” This manifest purpose, coupled with the Clause’s placement among the powers of the Article III courts, suggests that a technical, element-by-element test to determine whether a new crime is in all circumstances exactly the same as the crime of “treason” may be an overly formal approach to determining whether a national security prosecution deserves the special evidentiary protections the Treason Clause requires. Where a prosecution amounting to a charge that an American has aided an enemy of the United States implicates such basic freedoms, the Treason Clause may provide an additional constitutional basis for arguing that the courts must take special care in protecting against prosecutorial abuse.

Matters of Debate

More about Article III

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