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DNA Tests Free Japanese Man After 17 Years In Jail


Two years later, Toshikazu Sugaya, then 46-years-old, was sentenced by the local district court to life imprisonment based on DNA tests that indicated he might be the child’s killer. Despite having an appeal rejected in 2000, Sugaya maintained his innocence whilst serving many years in prison. However, in June 2009, after more than 17 years in detention, Sugaya was freed. Toshikazu Sugaya’s release from prison came as a result of fresh evidence arising from new tests.

Sugaya’s defence lawyers had repeatedly demanded that the accuracy of the original DNA tests were flawed and that new tests were essential in order to prove Sugaya’s innocence. Using samples of dried body fluid found on the deceased girl’s clothing, the tests showed that there was no match between these and Sugaya’s DNA. In other words, the incriminating fluid did not belong to Sugaya, thus the original DNA tests had been proved inaccurate. This raises at least two fundamental issues:

First, the fact that a conviction was made on the basis of DNA tests that were later proved inaccurate demonstrates how important it is for a court to consider a case in its entirety and not on any single point. Indeed, whilst scientific evidence is an extremely important aid in reaching a judgement, it must not be viewed in isolation of other material facts. Furthermore, eye witness reports, prosecution testimonies and the arguments of the defence team should not be accepted to a lesser extent than scientific opinion for the very reason identified in the case of Toshikazu Sugaya: science can get it wrong.

It is also crucial to recognise that scientific techniques are constantly improving, so what may be considered a certainty today might be disproved in the future. As technological breakthroughs are made, the ways in which scientific analysis is conducted also improves, so it is almost inevitable that newer techniques will cast some doubt over older methods. In the case of Sugaya, this process of scientific development cost him 17 years that can never be replaced and, in respect to the little girl who lost her life, it would seem that justice had not been delivered.

Tests the are based on DNA are, therefore, always open to scrutiny. However, the case of Sugaya also demonstrates that the science behind such tests is now at an incredibly advanced stage. To be able to examine dried fluid from the clothing of a girl who was killed almost 20 years ago in order to determine that a man who is now thought to have been wrongly convicted of her murder is innocent shows exceptional progress in tests. Furthermore, the inaccuracy of the first DNA tests should not detract from the value of testing generally. Indeed, modern science tells us that DNA governs various properties such as eye colour, bone density and stature. Strands of DNA comprise minute building-blocks that construct a human individual. PCR and RFLP DNA testing techniques have developed considerably in order to accurately match these strands with a unique individual.

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