The defeat of Nazi Germany brought to the forefront a problem the Allies had been grappling with for years -- what should be done with the Nazi leaders who had not been killed, committed suicide, or escaped into hiding? The Allies agreed that the top Nazi leadership could not allowed their liberty. But beyond that the Allies were in sharp disagreement. Some wanted to summarily execute the Nazi leadership without further ado. Others wanted to place the Nazi leaders on trial and punish them only if convicted. On August 8, 1945 the four principal Allies -- the United States, the U. S. S. R., France, and England--signed the London Charter, an international agreement setting up the International Military Tribunal for the trial of the major war criminals of the European Axis countries. Pressure from the United States, which strongly opposed summary executions of the Nazis, was the principal reason the Allies, after lively discussions, had decided to put the Nazi leaders on trial, rather than simply shoot them on the spot. The matter was of such grave importance to the United States that as early as May 2, 1945, five days before Germany's capitulation, President Truman appointed U. S. Supreme Court Justice Robert H. Jackson as chief prosecutor of major Axis war criminals, whereupon Jackson took a leave of absence from the Supreme Court.
Wilkes, Donald E. Jr., "The Trial of the Century--And of All Time" (2002). Popular Media. Paper 33.