American authorities widely undermined the prosecution of biological warfare war crimes in the Tokyo Trials, according to a book talk given by MIT professor Jeanne Guillemin on Sept. 25. The talk focused on how U.S. army intelligence refused to aid prosecutors and sometimes intentionally went against their wishes, derailing the prosecution of Japanese scientists who experimented on Chinese captives.

Japanese scientists, who were part of a biological warfare research center, conducted experiments with anthrax, cholera and the bubonic plague on live captives, and examined the effects by dissecting captives—alive or dead. The group also deployed the plague using low flying planes with plague-infected fleas to spread disease in different cities in China.

A graduate of the Heller School for Social Policy and Management, Tun Lwin, recounted his experience hearing his grandmother talk about the attacks. “I heard a story about the plague, at the time I was so young I did not know how that originated… but I remember my grandma told the story about how it wipes out whole villages and people did not know where the source comes from,” he said. “They only thought that it was from the rats…They believed it was caused by nature.”

Jeanne Guillemin gave the talk on her new book, “Hidden Atrocities: Japanese Germ Warfare and American Obstruction of Justice at the Tokyo Trial.” Guillemin is the senior advisor of the Massachusetts Institute of Technology (MIT) Security Studies Program and got her Ph.D. from Brandeis in 1973 in Sociology and Anthropology. She is the author of six books, mostly dealing with biological weapons such as anthrax.

She described some of the atrocities that took place in Japanese research centers, including vivisection and experimentation. The atrocities were buried by various American officials, and some were difficult to recognize as atrocities at all, such as the use of the plague as a biological weapon in China.

“See that’s the thing about biological weapons,” she said. “You could use them and people would say ‘oh that’s nature, that’s a natural occurrence…’ the causality is blurred… If somebody drops a bomb… you know what that is but with biological weapons you don’t know.”

Her talk explained that officials high up in the United States government, including General Douglas MacArthur, who oversaw the American occupation of Japan, knew about the atrocities and refused to prosecute, even specifically telling some Japanese scientists, such as General Shiro Ishii who ran the biological warfare unit. Guillemin said that prosecuting war crimes for the use of biological weapons would make it harder for the United States to use and develop their own programs, discouraging them to prosecute.

“Our biological weapons program in World War II…was second in funding as a weapons program only to the atomic weapons program,” she said. “It was vigorous, it was active and it was highly, highly secret. And it had branches all over the United States so we had a huge investment in biological weapons and we had a lesser investment in chemicals, but we did have chemical weapons.”

Guillemin related several incidents where U.S. army intelligence, commonly abbreviated as G-2, blocked access to Ishii and later removed the charges of biological warfare from the indictment. American personnel also made an agreement with Ishii and another Japanese doctor, Ryoichi Naito, that the United States would not prosecute them for war crimes.

Naito founded Green Cross Corp., a pharmaceutical firm based in Osaka, Japan, after World War II. He died in July 1982. His involvement in Unit 731, the name for the covert chemical and biological warfare research center, was reported by the Japan Times in 1998.