The Japanese war criminals of World War II were prosecuted in two parallel tracks: twenty-eight senior leaders tried in the Tokyo Trials before the International Military Tribunal for the Far East, and thousands of lower-ranking soldiers, officers, and camp personnel tried in regional military commissions across Asia and the Pacific. The Tokyo proceedings produced seven executions, sixteen life sentences, and a body of law that still governs command responsibility today. They also left large categories of wrongdoing untouched, and within a decade of the verdicts almost every surviving convict had been released.
How the Charges Were Structured
The Charter of the International Military Tribunal for the Far East sorted the offenses into three classes. Class A covered crimes against peace: planning, launching, or waging aggressive war in violation of international treaties. Class B covered conventional war crimes, meaning violations of the established laws and customs of war, including mistreatment of prisoners and the killing of civilians in occupied territory. Class C covered crimes against humanity: large-scale murder, enslavement, deportation, and other systematic attacks on civilian populations.1University of Oslo. International Military Tribunal for the Far East Charter
The three classes were not a hierarchy of severity. They were a way to capture the full chain of responsibility, from the cabinet ministers who set policy to the guards who ran prison camps. A single defendant could face charges in more than one category.
The Tokyo Tribunal and Its Verdicts
General Douglas MacArthur established the tribunal on January 19, 1946, with judges seated from eleven Allied nations, including the United States, China, the United Kingdom, the Soviet Union, Australia, France, the Netherlands, India, and the Philippines.2The National WWII Museum. Tokyo War Crimes Trial The indictment period reached back to 1928, reflecting the prosecution’s theory that Japan’s aggression was not a series of isolated decisions but a sustained conspiracy spanning nearly two decades. Proceedings opened in May 1946 and ran for more than two years, producing a judgment that exceeded one thousand pages.3The United States Army. The Tokyo Trials
Twenty-eight defendants were arraigned on Class A charges. Two died of natural causes during the trial, and one was found mentally unfit, leaving twenty-five for final judgment.4Peace Palace Library. The Tokyo Trial The most prominent figure was Hideki Tojo, who had served as Prime Minister and Minister of the Army during the critical years of the Pacific War.
Seven defendants were sentenced to death and hanged at Sugamo Prison on December 23, 1948:
- Hideki Tojo, former Prime Minister
- General Kenji Doihara, head of intelligence operations in Manchuria
- Koki Hirota, former prime minister and foreign minister
- General Seishiro Itagaki, former war minister
- General Heitaro Kimura, commander of forces in Burma
- Lieutenant General Akira Muto
- General Iwane Matsui, who bore command responsibility for the atrocities at Nanjing
Sixteen defendants received life imprisonment. Foreign Minister Shigenori Togo was sentenced to twenty years, and Foreign Minister Mamoru Shigemitsu received seven. Every remaining defendant was found guilty on at least some counts.4Peace Palace Library. The Tokyo Trial
Nanjing and the Command Responsibility Doctrine
The tribunal’s treatment of the 1937 Nanjing Massacre produced one of the most durable legal principles to emerge from the trials. When Japanese forces captured the Chinese capital, soldiers carried out weeks of mass killings, sexual violence, and looting against the civilian population. The tribunal found that General Iwane Matsui “organized the wholesale murder of male civilians” under the pretext that Chinese soldiers had discarded their uniforms and blended into the population.
Matsui had issued orders requiring proper conduct, but those orders had no effect. The tribunal found that he knew what was happening and “did nothing, or nothing effective to abate these horrors.” His knowledge combined with his failure to act amounted to criminal negligence, and he was sentenced to death. Former Foreign Minister Koki Hirota was likewise convicted for inaction, with the tribunal finding he had been “content to rely on assurances which he knew were not being implemented while two hundred thousands of murders, violations of women, and other atrocities were being committed daily.”
The principle these convictions established is the command responsibility doctrine: a commanding officer who is aware of war crimes committed by subordinates and fails to act to prevent or punish them can be held personally liable. The U.S. Supreme Court affirmed the same standard in the related case of General Tomoyuki Yamashita, tried and executed for failing to control Japanese forces during the Manila massacre. The Court held that the law of war “imposes on an army commander a duty to take such appropriate measures as are within his power to control the troops under his command.”5Justia. In re Yamashita, 327 US 1 (1946) That standard remains a cornerstone of international humanitarian law.
The Regional Trials
Tokyo handled only the senior leadership. Thousands of additional trials dealt with the soldiers, guards, and field officers who carried out specific atrocities. Military commissions operated at more than fifty locations across Asia and the Pacific, with major centers in Yokohama, Manila, Singapore, and sites throughout the former Dutch East Indies and China.6University of Hawaiʻi at Mānoa. Trial Records
The exact count remains contested. Japanese government records compiled between the 1950s and early 1970s put the figure at roughly 5,700 defendants, with approximately 900 receiving death sentences, though researchers have noted significant discrepancies between Japanese and Allied data.6University of Hawaiʻi at Mānoa. Trial Records Charges typically covered the torture of detainees, execution of captured airmen, imposition of forced labor on civilians, and the running of prison camps where starvation and disease killed thousands. The scale of prisoner mistreatment was its own indictment: 35,756 of the 132,134 Allied servicemen held in Japanese captivity died, a fatality rate of roughly 27 percent. The comparable figure for Western Allied prisoners in German custody was approximately 4 percent.
The Bataan Death March
One of the most prominent regional prosecutions concerned the Bataan Death March of April 1942. Approximately 76,000 prisoners of war, roughly 66,000 Filipinos and 10,000 Americans, were forced to march some sixty miles after the fall of Bataan. Thousands died from exhaustion, disease, and deliberate killings along the route. Lieutenant General Masaharu Homma, who had commanded the Japanese invasion forces in the Philippines, was indicted on 48 counts of violating the international rules of war. He pleaded not guilty, claiming he had only “a vague notion” of the march and had neither ordered nor condoned the abuses. A U.S. Army military commission in Manila convicted him, and he was executed by firing squad on April 3, 1946.
The Burma-Thailand Railway
The construction of the Burma-Thailand Railway produced some of the war’s most notorious forced labor crimes. The Japanese military used Allied prisoners and conscripted Asian laborers to build a rail link through dense jungle and mountainous terrain. Among Allied POWs, death rates ranged from roughly 15 percent for Dutch prisoners to 22 percent for British prisoners on the railway. The toll on Asian forced laborers, known as romusha, was far worse. Up to 90,000 are estimated to have died. They received almost no medical care, lived in overcrowded and unsanitary camps, and were driven by overseers who held absolute power over them.7Anzac Portal. Prisoners and Labourers on the Burma-Thailand Railway
What the Trials Did Not Reach
The limits of the prosecutions are as important as the convictions. Three categories of wrongdoing were largely or entirely passed over.
Unit 731
Unit 731 was a covert biological and chemical warfare research program operated by the Japanese military in Manchuria. Under the direction of General Shiro Ishii, the unit conducted lethal experiments on living prisoners, including deliberate infection with plague, cholera, and anthrax, as well as vivisection without anesthesia. Thousands of prisoners were killed in the facility itself, and biological weapons developed by the unit were deployed against Chinese civilian populations, with estimated death tolls reaching into the hundreds of thousands.
None of the Unit 731 researchers were prosecuted by the United States. Declassified documents from the National Archives show that MacArthur’s intelligence staff granted “documentary immunity from war crimes” to Ishii and other researchers “in exchange for cooperation and full disclosure” of their experimental data. The State-War-Navy Coordinating Committee concluded that the intelligence value of the biological warfare research “outweighed war crimes prosecution.”8National Archives. Select Documents on Japanese War Crimes The State Department objected, warning that immunity would be “a source of serious embarrassment to the United States,” but was overruled. The only prosecution of Unit 731 personnel came from the Soviet Union, which held the Khabarovsk trial in late 1949 and convicted twelve Japanese servicemen. The Western powers dismissed those proceedings as communist propaganda at the time.
The Comfort Women System
The Japanese military operated a system of sexual slavery, in which women were forced to serve in so-called “comfort stations” near the front lines, from the early 1930s through the end of the war. A 1942 Japanese War Ministry report recorded approximately 400 such facilities across occupied territories. Estimates of the total number of women forced into the system range from roughly 20,000 to over 200,000.9Digital Museum: The Comfort Women Issue and the Asian Women’s Fund. Number of Comfort Stations and Comfort Women A UN report cited in the same research found that only about 25 percent of the women survived.
The Tokyo Tribunal did not prosecute anyone for operating the system. The only wartime prosecution related to forced sexual slavery was the 1948 Batavia trial, conducted by a Dutch military court in the former Dutch East Indies, which addressed the forced prostitution of Dutch women interned in Japanese camps. Army Major Okada was sentenced to death, and eleven others received prison terms ranging from two to twenty years.10Digital Museum: The Comfort Women Issue and the Asian Women’s Fund. Women Made to Become Comfort Women – Netherlands The vast majority of victims, particularly Asian women, received no judicial recognition.
The Emperor
Emperor Hirohito was never indicted, never testified, and was insulated from the tribunal entirely. The IMTFE Charter, unlike the Nuremberg Charter, conspicuously omitted any provision permitting prosecution of heads of state.11Texas A&M Law Scholarship. The Emperor’s Clothes: Evaluating Head of State Immunity Under International Law MacArthur’s reasoning was strategic. He warned Washington that indicting the Emperor would “unquestionably cause a tremendous convulsion among the Japanese people,” predicted that the government would break down and resistance devolve into guerrilla warfare, and estimated that occupation forces would need to increase to a minimum of one million troops. He also feared destroying the imperial institution would open the door to communist revolution. MacArthur added that “no specific and tangible evidence has been uncovered” to directly connect the Emperor to the political decisions of the prior decade, and that his role appeared “largely ministerial and automatically responsive to the advice of his counsellors.”12Office of the Historian. Foreign Relations of the United States, 1946, The Far East, Volume VIII Other members of the imperial family, including Prince Asaka, who held command authority during the Nanjing Massacre, similarly avoided prosecution.
The Dissenting Judges
The tribunal’s judgment was not unanimous. The most famous dissent came from Justice Radhabinod Pal of India, whose opinion exceeded 1,230 pages. Pal rejected the legal validity of the charges of crimes against peace and crimes against humanity, calling them inventions created “for the satisfaction of a thirst for revenge.” He placed Japanese actions in the context of Western colonialism and described the atomic bombings of Hiroshima and Nagasaki as “among the most wantonly criminal acts of World War II.” Pal did not deny that Japanese forces committed war crimes. He acknowledged atrocities including Nanjing but argued they should have been prosecuted under the conventional categories rather than the contested Class A charges, which he viewed as retroactive law.13The National WWII Museum. Justice Radhabinod Pal and the Tokyo Tribunal
Justice Henri Bernard of France filed a separate opinion arguing that the proceedings were fundamentally flawed because Hirohito was not on trial. He also noted that the eleven judges were never called together to orally discuss the judgment. Justice B.V.A. Röling of the Netherlands dissented on the sentences, arguing that five of the accused, most notably former foreign ministers Hirota and Shigemitsu, should have been acquitted. Justice Sir William Webb of Australia, the tribunal’s president, prepared a separate opinion of more than 600 pages before submitting a shorter version.
Early Release and Political Rehabilitation
The sentences did not hold for long. The onset of the Cold War shifted American strategic priorities in Asia, and Japan transformed from defeated enemy to critical ally against communist expansion. Under Article 11 of the 1951 San Francisco Peace Treaty, Japan formally accepted the judgments of the war crimes tribunals but was given a role in the clemency process. The treaty specified that clemency, reduced sentences, or parole could be granted only with the approval of the governments that had imposed the sentences, and on Japan’s recommendation.14United Nations. Treaty of Peace with Japan
Internal State Department deliberations from 1955 reveal that the U.S. government considered a mass parole of all 264 Japanese war criminals still in American custody. The Secretary of State rejected the proposal, reasoning that mass parole “would seem to be an admission by the United States that the trials had been a mistake” and would embarrass allied nations that had opposed accelerated releases.15Office of the Historian. Foreign Relations of the United States, 1955-57, Volume XXIII, Part 1 Even so, the clemency and parole process steadily emptied the prisons. By the end of the 1950s, virtually all convicted war criminals had been released.
Some went further than freedom. Nobusuke Kishi, who had been arrested as a suspected Class A war criminal in 1945, was released without trial in 1948 during a broader shift in occupation policy. In 1957 he became Japan’s Prime Minister.