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Aaron Burr and the Definition of Treason

Aaron Burr and the Definition of Treason


Beginnings. Aaron Burr, in Henry Adamss words, impressed with favor all who first met him. Burr, grandson of the great theologian Jonathan Edwards, served as a colonel in the Continental Army and later studied law under Tapping Reeve in Connecticut. An intensely political and highly ambitious man, Burr centered his political career in New York. He served in the New York Assembly (1784) and as state attorney general (1789) before being elected to the U.S. Senate in 1791. In 1800, as the designated Republican candidate for vice president, Burr received the same number of electoral votes as Thomas Jefferson. Under the Constitution the House of Representatives had to decide between the two candidates. It took thirty-six ballots cast over nearly a week for Jefferson to receive the required majority of states. Burr took office as vice president but was estranged from Jefferson and had no role in the administration. Rather than seek reelection in 1804, he ran unsuccessfully for governor of New York. His service as presiding officer during the trial of Associate Justice Chase in February 1805 (his last month in office) was perhaps the high point of his service as vice president.

Conspiracy. Once out of office Burr sought to chart a course back to power. Distrusted by Jefferson and hated by Federalists for killing Alexander Hamilton in a duel in 1804, Burr traveled west. With his easy charm and famous name he befriended many, including Henry Clay and Andrew Jackson. In what is now West Virginia he made the acquaintance of Harman Blennerhassett, an Irish immigrant who owned an island in the Ohio River. Blennerhassett offered Burr friendship, accommodations, and political support. Burr had a potentially more potent ally in Gen. James Wilkinson, governor of the Louisiana Territory. Wilkinson was a man of large ambitions, and at some point he saw that an alliance with Burr would enable him to play all sides of a treacherous game. Although he would later renounce Burr and deny any complicity in Burrs goals, it seems clear that Wilkinsons offer of support gave Burr the initial boost he needed to pursue his goals. Even today there is only speculation about what Burr was really up to. The most charitable version of events has him preparing to lead an effort to liberate lands under Spanish rule. His ultimate goals:

free Mexico and, eventually, Central and South America. Others believed that Burr really wanted to separate the states and territories west of the Alleghenies from the Union. Whether or not he meant to set himself up as leader of a new American Empire is, at best, ambiguous.

Scene of Depravity. If Burr was engaged in conspiracy to disunite the nation, it was one of the most open secrets of the day. Rumors flew about across the nation and in official dispatches from British and Spanish ministers. On 22 January 1807, aware that Burrs conspiracy was the talk of Washington, D.C., President Jefferson sent a special message to Congress outlining the machinations and preparing Congress for the treason trial that would follow. Jeffersons message to Congress described the alleged conspiracy to divide the Union as this scene of depravity and referred to Burrs intentions as an illegal combination against the peace and safety of the Union. Jefferson declared that although it was difficult to sift out the real facts, Burrs guilt is placed beyond question.

Capture. When Burr heard rumors of his supposed intentions, he wrote a friend that If there exists any design to separate the western from the eastern states, I am totally ignorant of it. I never harbored or expressed any such intention to anyone, nor did any person ever intimate such design to me. In this atmosphere of rumor and accusation government officials in Washington were prepared to try Burr for treason. First, though, he had to be found, and sixty men were sent down the Mississippi River. Burr claimed to be on his way to settle new lands in the western territories. Others believed Burr and his band of followers were bent on using force to detach American territory from the Union. Federal officials detained Burr in the Mississippi Territory and charged him with conspiracy against the United States. A grand jury exonerated him, but Burr feared for his life and went into hiding. U.S. marshals then caught him again and brought him east for trial.

Treason on Trial. In Washington two of Burrs accomplices, Dr. Justus Erich Bollman and Samuel Swartwout, were being tried for treason by virtue of their support for Burrs activities. The charges against these men were based on an alleged conspiracy hatched with Burr on Blennerhassett Island. Chief Justice John Marshall heard the case against Bollman and Swartwout and released the men for lack of evidence. Marshall noted the constitutional definition of treasonlevying war against the United States or adhering to their enemies, giving them aid and comfortand declared that conspiracy is not treason. The chief justice believed that there must be an actual assembling of men for the treasonable purpose, to constitute a levying of war. Without any such evidence, he had no choice but to release Bollman and Swartwout. Marshall was setting the standard for the upcoming treason trial of Burr. If the government failed to come forward with real evidence of an effort to levy war, it faced certain defeat in court.

Executive Privilege. Burrs trial took place in Richmond, Virginia. The former vice president assembled an impressive defense team, including Luther Martin, who had defended Samuel Chase during his 1805 impeachment trial. Burrs lawyers claimed that they required certain documents in the presidents possession in order to put their case forward. The government sought to block issuance of a subpoena on the basis that the president was not subject to such a writ by a claim of executive privilege. Marshall, however, ruled that the subpoena could be issued. The president was as much subject to the law as any citizen, but the court would give due consideration to his office and prevent vexatious and unnecessary subpoenas from being issued. When Marshall issued the subpoena, Jefferson ignored it.

The Burr Trial. The trial finally began on 3 August 1807. Marshall reminded the governments lawyers that Treason can be perpetrated only in open day and in the eye of the world. Burrs attorneys asked that the government be required to prove the act of treason. The government could not do so: it admitted that Burr was not present when his allies on Blennerhassett Island discussed the conspiracy to take up arms against the United States. The governments witnesses could not testify to firsthand knowledge of Burrs alleged traitorous behavior. Because they were unable to say they had seen Burr commit any overt acts against the government, they actually helped Burrs case. Marshalls charge to the jury required acquittal. The overt act of levying war must be proved by two witnesses. It is not proved by a single witness. Burr was found not guilty.

Conclusion. Aaron Burr was no saint and Thomas Jefferson no reckless political partisan. Yet, when the president sought to use the constitutional crime of treason to vanquish his adversary, he was pushing the use of the Constitution to its limits. John Marshall, no friend of the man who murdered Alexander Hamilton, nevertheless was determined to assure Burr a fair trial. His strict interpretation of the language of the Constitution defining treason prevented the use of the law as a way to harm political opponents. Marshall earned the enmity of the president, but he struck a blow for the proper and prudent use of the Constitution to achieve political ends. The American nation was young and its judicial system largely untested, but in this important instance it worked well.


Thomas Perkins Abernethy, The Burr Conspiracy (New York: Oxford University Press, 1954);

Henry Adams, History of the United States of America (New York: Scribners, 18891891);

Jean Edward Smith, John Marshall: Definer of a Nation (New York: Holt, 1996).

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