The Rosenberg Trial

Federal Trials and Great Debates 

in United States History

Case Summary:

• Julius and Ethel Rosenberg, a Communist couple living in New York City, were accused in 1950 

of conspiracy to commit espionage by transmitting information about the atomic bomb to the 

Soviet Union.

• The primary witnesses against the Rosenbergs were Ethel’s brother and his wife, David and Ruth 

Greenglass.

• The Rosenbergs were convicted and sentenced to death; after their multiple appeals and 

requests for clemency were denied, they were executed in 1953.

• The case and its legacy epitomized the gulf between those who saw the Red Scare as an 

overreaction and those who believed that Communists had posed an existential threat to the 

nation.

History of the Case:

The early 1950s were the high point of the “Red Scare”—a time when many Americans feared subversion 

by Communists within the United States who sympathized with the nation’s Cold War rival, the Soviet 

Union. International developments following the end of World War II, including the Soviets’ backing of a 

1948 Communist coup in Czechoslovakia and the 1949 Communist takeover of China, heightened fears 

that Communists were aiming for global supremacy. The Soviets’ development of an atomic bomb in 

1949, ending the American monopoly on nuclear weapons, fueled anxieties that the Cold War could 

quickly turn into a catastrophic conflict. At the same time, events at home led many to believe that 

Communists were infiltrating the U.S. government and spying on behalf of the Soviets. Former State 

Department official Alger Hiss, accused of being a Communist spy, was convicted of perjury in 1950; 

Senator Joseph McCarthy became famous for his claims of widespread Communist infiltration of the 

federal government; leaders of the Communist Party USA were prosecuted for conspiring to advocate 

revolution; and the House Un-American Activities Committee held hearings to investigate possible 

Communist influence in Hollywood and elsewhere.

In the midst of this heightened concern about Communist subversion, Julius and Ethel Rosenberg 

were charged with conspiracy to commit espionage on behalf of the Soviet Union. They were alleged to 

have transmitted to the Soviets material related to perhaps the greatest object of American anxiety: the 

atomic bomb. A chain of arrests beginning in early 1950 led the authorities to David Greenglass, a U.S. 

Army officer who was alleged to have stolen classified information from the atomic bomb program in Los 

Alamos, New Mexico, where he worked. Greenglass claimed that he and his wife, Ruth, had been coaxed 

into espionage by his sister, Ethel Rosenberg, and her husband, Julius, both of whom were Communists.

It was the Rosenbergs, he said, to whom he passed the information he stole, so that they could deliver it 

to the Soviets. Although the government had little evidence of Ethel’s involvement, FBI Director J. Edgar 

Hoover wanted her charged as a means to pressure Julius to name other members of the spy ring.

After David Greenglass pleaded guilty, the Rosenbergs were tried in March 1951, along with codefendant Morton Sobell, before Judge Irving Kaufman of the U.S. District Court for the Southern District 

of New York. Kaufman was a staunch anti-Communist who had previously given the maximum sentence 

to Communists convicted of lying to a grand jury investigating espionage, accusing them of attempting to 

“destroy” the United States. During the Rosenbergs’ three-week trial, David and Ruth Greenglass 

provided the only testimony directly linking the Rosenbergs to espionage. Many years later, David 

Greenglass admitted that he had committed perjury by corroborating his wife’s testimony about Ethel, 

without which she would most likely not have been convicted.
After the jury convicted all three defendants of violating the Espionage Act of 1917, Judge 

Kaufman told the jurors, “My opinion is that your verdict is a correct verdict.” Soon after, the judge 

sentenced the Rosenbergs to death while sentencing Morton Sobell to 30 years in prison. Speaking of the 

“life and death” struggle between the United States and the Soviet Union, Kaufman characterized the 

Rosenbergs’ crime as “worse than murder,” and blamed them in part for the outbreak of the Korean War. 

David Greenglass received a lighter sentence of 15 years in prison as a result of his cooperation with the 

government. While Judge Kaufman stated in court that he had not asked the prosecution for a sentencing 

recommendation, he had privately solicited the view of the prosecution, other judges, and Department of 

Justice officials.

For two years after being sentenced, the Rosenbergs fought to avoid execution. Claiming that 

various aspects of their trial had been unfair—and in particular that extensive newspaper coverage and a 

hostile trial judge had unfairly prejudiced the jurors—they appealed their convictions and sentences to the 

U.S. Court of Appeals for the Second Circuit and the Supreme Court of the United States. All of their 

appeals failed, as did a request for executive clemency directed to President Harry Truman, which Dwight 

Eisenhower rejected after assuming the presidency. Shortly before the scheduled execution date, 

Supreme Court Justice William O. Douglas issued a stay of execution, but the full Supreme Court voted 

6-3 to lift the stay only two days later. On June 19, 1953, Julius and Ethel Rosenberg were executed in 

the electric chair at Sing Sing Prison in Ossining, New York.

The Rosenberg case left a complicated legacy. On one hand, the Rosenbergs’ conviction and 

execution on thin evidence, at least some of which was false, stands as a testament to the antiCommunist hysteria that gripped the United States in the 1950s. On the other hand, the opening of Soviet 

archives in the 1990s following the collapse of the Soviet Union revealed that the Communist Party USA 

was actively involved in Soviet espionage in the United States in the 1930s and 1940s. Gathering 

information about the atomic bomb was, after 1941, the Party’s top espionage priority. Julius Rosenberg, 

this later-released evidence showed, did spy for the Soviets. Ethel, while most likely aware of her 

husband’s actions, probably was not herself a spy. The information that Julius gave to the Soviets, 

characterized during the trial as “the secret of the atomic bomb,” is considered by most scholars to have 

been of little value. To the present day, the case has served as an ideological battleground for those who 

denounced what they believed to be government persecution arising from the Red Scare and those who 

believed that the government had acted appropriately in response to a grave threat to the United States.

Legal Issues:

• Were the Rosenbergs denied a fair trial because of the prosecution’s use of perjured testimony 

from David Greenglass and the admission of evidence of the Rosenbergs’ membership in the 

Communist Party?

• Did Judge Irving Kaufman’s bias against the Rosenbergs make their trial unfair?

• Did publicity before and during the trial—including a press conference at which the prosecutor 

announced the arrest of a Rosenberg and Sobell associate—deprive the Rosenbergs of a fair 

trial?

Questions for Discussion:

• Was it possible for avowed Communists accused of atomic espionage for the Soviets to receive a 

fair trial during the Red Scare?

• What role should the judicial system play in maintaining a balance between civil liberties and 

national security, particularly in a time of perceived crisis?

• In what modern contexts might the Rosenberg case and its lessons be particularly relevant?