While Sir Geoffrey Lawrence of Britain was the judge who was chosen to serve as the president of the court, arguably, the most prominent of the judges at the trial was his American counterpart, Francis Biddle.
Before the trial, Biddle had been Attorney General of the United States but had been asked to resign by Truman earlier in 1945.

Some accounts argue that Truman had appointed Biddle as the main American judge for the trial as an apology for asking for his resignation.
Ironically, Biddle was known during his time as Attorney General for opposing the idea of prosecuting Nazi leaders for crimes committed before the beginning of the war, even sending out a memorandum on 5 January 1945 on the subject.
The note also expressed Biddle's opinion that instead of proceeding with the original plan for prosecuting entire organizations, there should simply be more trials that would prosecute specific offenders.

Biddle soon changed his mind, as he approved a modified version of the plan on 21 January 1945, likely due to time constraints, since the trial would be one of the main issues which were to be discussed at Yalta.
At trial, the Nuremberg tribunal ruled that any member of an organization convicted of war crimes, such as the SS or Gestapo, who had joined after 1939 would be considered a war criminal.
Biddle managed to convince the other judges to make an exemption for any member who was drafted or had no knowledge of the crimes being committed by these organizations.

Justice Robert H. Jackson played an important role in not only the trial itself but also in the creation of the International Military Tribunal, as he led the American delegation to London that, in the summer of 1945, argued in favor of prosecuting the Nazi leadership as a criminal conspiracy.
According to Airey Neave, Jackson was also the one behind the prosecution's decision to include membership in any of the six criminal organizations in the indictments at the trial, though the IMT rejected this because it was wholly without precedent in either international law or the domestic laws of any of the Allies.
Jackson also attempted to have Alfried Krupp be tried in place of his father, Gustav and even suggested that Alfried volunteer be tried in his father's place.
Both proposals were rejected by the IMT, particularly by Lawrence and Biddle, and some sources indicate that this resulted in Jackson being viewed unfavorably by the latter.

Thomas Dodd was a prosecutor for the United States.
There was an immense amount of evidence backing the prosecutors' case, especially since meticulous records of the Nazis' actions had been kept.
There were records taken in by the prosecutors that had signatures from specific Nazis signing for everything from stationery supplies to Zyklon B gas, which was used to kill the inmates of the death camps.
Thomas Dodd showed a series of pictures to the courtroom after reading through the documents of crimes committed by the defendants.
The showing consisted of pictures displaying the atrocities performed by the defendants.
The pictures had been gathered when the inmates were liberated from the concentration camps.

Henry F. Gerecke, a Lutheran pastor, and Sixtus O'Connor, a Roman Catholic priest, were sent to minister to the Nazi defendants.
Photographs of the trial were taken by a team of about a dozen US Army still photographers, under the direction of chief photographer Ray D'Addario.
While Sir Geoffrey Lawrence of Britain was the judge who was chosen to serve as the president of the court, arguably, the most prominent of the judges at the trial was his American counterpart, Francis Biddle. Before the trial, Biddle had been Attorney General of the United States but had been asked to resign by Truman earlier in 1945.
Some accounts argue that Truman had appointed Biddle as the main American judge for the trial as an apology for asking for his resignation. Ironically, Biddle was known during his time as Attorney General for opposing the idea of prosecuting Nazi leaders for crimes committed before the beginning of the war, even sending out a memorandum on 5 January 1945 on the subject. The note also expressed Biddle's opinion that instead of proceeding with the original plan for prosecuting entire organizations, there should simply be more trials that would prosecute specific offenders.
Biddle soon changed his mind, as he approved a modified version of the plan on 21 January 1945, likely due to time constraints, since the trial would be one of the main issues which were to be discussed at Yalta. At trial, the Nuremberg tribunal ruled that any member of an organization convicted of war crimes, such as the SS or Gestapo, who had joined after 1939 would be considered a war criminal. Biddle managed to convince the other judges to make an exemption for any member who was drafted or had no knowledge of the crimes being committed by these organizations.
Justice Robert H. Jackson played an important role in not only the trial itself but also in the creation of the International Military Tribunal, as he led the American delegation to London that, in the summer of 1945, argued in favor of prosecuting the Nazi leadership as a criminal conspiracy. According to Airey Neave, Jackson was also the one behind the prosecution's decision to include membership in any of the six criminal organizations in the indictments at the trial, though the IMT rejected this because it was wholly without precedent in either international law or the domestic laws of any of the Allies. Jackson also attempted to have Alfried Krupp be tried in place of his father, Gustav and even suggested that Alfried volunteer be tried in his father's place. Both proposals were rejected by the IMT, particularly by Lawrence and Biddle, and some sources indicate that this resulted in Jackson being viewed unfavorably by the latter.
Thomas Dodd was a prosecutor for the United States. There was an immense amount of evidence backing the prosecutors' case, especially since meticulous records of the Nazis' actions had been kept. There were records taken in by the prosecutors that had signatures from specific Nazis signing for everything from stationery supplies to Zyklon B gas, which was used to kill the inmates of the death camps. Thomas Dodd showed a series of pictures to the courtroom after reading through the documents of crimes committed by the defendants. The showing consisted of pictures displaying the atrocities performed by the defendants. The pictures had been gathered when the inmates were liberated from the concentration camps.
Henry F. Gerecke, a Lutheran pastor, and Sixtus O'Connor, a Roman Catholic priest, were sent to minister to the Nazi defendants. Photographs of the trial were taken by a team of about a dozen US Army still photographers, under the direction of chief photographer Ray D'Addario.
Nuremberg trials