Page 91 - Unit 731 Testimony

belief in his guilt. Even survivors brought in to view Hirasawa in a police
lineup said he did not resemble the man who came to the bank. Soon after
the Teigin Incident, the law was changed so that a confession on its own

would not be considered a reasonable standard of proof to convict a
defendant. In contemporary times, there would probably not be enough
evidence against Hirasawa to convict him.
Even the evidence that the state did have proved troublesome—and
suspect. Keio University and Tokyo University each performed autopsies on

six of the twelve victims chosen at random. Keio found that the poison was
acetone cyanohydrin. Two to three months later, Tokyo University issued its
findings: the poison was potassium cyanide. The sequence of events
surrounding the release of these conflicting autopsy reports is one of the
elements that casts an ever darker shadow over the findings, and
strengthens suspicions of the incident's connection with Unit 731. The Keio

results naming the murder poison as acetone cyanohydrin were released
before Hirasawa was arrested. Then, some two to three months after
Hirasawa's arrest, Tokyo University came out with its findings that the
poison used was potassium cyanide.

The type of poison used in the crime was a crucial factor in
determining the direction in which the finger of accusation would point.
Potassium cyanide was a poison with a long history, and it would not be
unavailable to someone who really wanted it. An instantaneously acting
poison, it would have been unsuitable for a sabotagestyle operation: the
victim would succumb immediately upon ingesting the poison, and the

identity of the poisoner would be obvious. Accordingly, the Tokyo
University findings left room for suspicion.
On the other hand, acetone cyanohydrin was a poison with a much
different history and set of characteristics. The Japanese army had been
searching for a poison that would not take effect until a short time after the

victim drank it. It had tackled this problem at Noborito Army Research
Center in Kawasaki, a laboratory for developing special weapons operating
under the same secret army umbrella as Unit 731. Ishii's unit worked
closely with Noborito by conducting human tests for products under
development. Acetone cyanohydrin was produced under the Noborito

poison development program. It had been tested on Chinese prisoners by
the Ishii organization under the same ruse used at Teigin, the claim that it
was a preventive medicine against a communicable disease. The test