In June 2009, this column mentioned a TBS news report about the DNA testing method that resulted in the 1992 conviction of Toshikazu Sugaya for the 1990 murder of 4-year-old Mami Matsuda in Ashikaga, Tochigi Prefecture. Sugaya was sentenced to an indefinite prison term but was released last year after his lawyers finally convinced a court to accept new evidence that showed the DNA testing at the time was faulty, and that new tests prove that Sugaya couldn’t be the murderer. In that column I commended the thoroughness of the TBS Special but with a reservation: Since the lawyers had known about the faulty DNA for years, why didn’t TBS broadcast a report sooner?

One TV journalist has been conveying his own reservations about the Sugaya conviction since 1996, when he started investigating the disappearance of another 4-year-old girl in the city of Ota, Gunma Prefecture. Nihon TV reporter Kiyoshi Shimizu noticed similarities not only to the Matsuda murder but also to three other unsolved disappearances that happened in either Ota or Ashikaga, which are neighbor cities.

Shimizu has been following the Ashikaga case assiduously ever since, and NTV airs his occasional reports as part of network news and wide shows. The latest was broadcast a week ago on the late night program “NNN Document.” In it, Shimizu wondered why, with all the available leads, the police aren’t now looking for the real murderer of Mami Matsuda.

Sugaya himself says he cannot attain closure until he sees the killer brought to justice. His sense of frustration is compounded by the fact that, while Tochigi district court judges have apologized to him, prosecutors have not. On the program, Shimizu has a voice actor re-create the tape-recorded “confession” that prosecutor Kenji Morikawa elicited from Sugaya based on the results of the DNA testing, which Morikawa repeatedly and calmly explained proves that “no one else” could have killed the girl. Later, Sugaya recanted the confession, but the judge and every subsequent judge up until the retrial in 2009 believed the DNA results, the only evidence the prosecution had.

The technician who retested the DNA sample, taken from a semen stain on Mami Matsuda’s discarded T-shirt, testified last year that he checked it against Sugaya’s sample “400 times” using a computer (the original testing was done “by eye”) and never found a match. Prosecutors simply said the technician was “wrong” but didn’t offer a reason for their assertion.

When asked by politicians or the media why they haven’t reopened the murder investigation, prosecutors as well as the justice ministry have stated that the statute of limitations has run out. Shimizu says this is specious reasoning. Statutes of limitations are based on the idea that an investigation has been ongoing during the period stipulated in the statute, but the investigation of the Ashikaga murder case stopped in 1992 with the arrest of Sugaya.

The matter became even more perplexing when Mami’s mother asked the police for her daughter’s T-shirt, since they say that the case is closed. Usually, the authorities offer to return such property to the family of a victim, but the police refused, claiming that they need to keep the evidence “in case the real perpetrator appears”; meaning, presumably, that the murderer voluntarily turns himself in after all this time. It doesn’t mean the police will actively look for him. Perhaps fearful that the mother will use the T-shirt as evidence in a civil suit against the police, prosecutors say that they received permission from Mami’s father to keep it. As is often the situation in drawn-out cases involving murdered children, Mami’s parents divorced some years ago.

But a civil suit is the least of the justice ministry’s problems. As some media reported during Sugaya’s retrial, the same outdated DNA testing method that resulted in his wrongful imprisonment was used to convict Michitoshi Kuma of killing two girls in 1992 in Fukuoka Prefecture. Unlike Sugaya, Kuma never confessed, maintaining his innocence right up to his execution in 2008, less than three years after his final appeal was rejected and about eight months before Sugaya’s case was reopened. If prosecutors and the justice ministry admit openly that the DNA testing method they relied on was inherently faulty, they would have to revisit Kuma’s case and face the possibility that a new inquiry will reveal that they sent an innocent man to his death.

Writing in a three-part series in the monthly magazine Bungei Shunju this fall, Shimizu implies that Mami Matsuda’s killer can probably be found without much trouble. Having visited the Ota-Ashikaga area “more than a hundred times” in the past 14 years, he re-creates Mami’s kidnapping and links it to four other murder-abductions of little girls in the area since 1979, something the local police have never conjectured, at least not publicly. He has talked to numerous witnesses who say they saw the same man walking with little girls around the times the disappearances took place, and knows that the police investigated a suspect matching their description’s of him before arresting Sugaya. Since there’s a good possibility the killer is still at large, by not reopening the investigation the police are neglecting their responsibility to serve and protect.

A former photographer for the defunct news magazine Focus who on Nov. 5 received an Excellence in Reporting award from a broadcasters’ association, Shimizu is the only journalist who has done this sort of leg work. He is also the only journalist granted interviews by Mami Matsuda’s mother, who, understandably, has no reason to trust news media that unquestioningly bought the police version of her daughter’s death until only a few years ago. She herself never believed Sugaya’s confession, but says the police didn’t ask for her opinion back then. It’s unlikely they’ll seek Shimizu’s now.

Phillip Brasor blogs at philipbrasor.com