This week, police in Saga Prefecture, Japan, admitted that an employee falsified crucial DNA evidence in 130 cases. The incident raises serious questions about prefectural police’s quality control procedures.

“I made it look like I was working”

Ogishi, Saga PrefectureOgishi, Saga Prefecture. (Picture: e46av22 / PIXTA(ピクスタ))

The controversy centers around a 40-something forensic examiner in Saga. The employee, who had been in charge of processing DNA evidence for seven years, reportedly falsified evidence in 130 cases.

Officials say the examiner, in some cases, reported negative DNA results without running any actual tests. In other cases, they replaced lost materials with numbers from other cases, falsifying the results.

NHK News reports that the cases involved charges of stalking, drug use, and even attempted murder.

Prefectural police fired the employee for falsifying evidence. They also filed charges with prosecutors involving 13 cases, charging the employee with hiding evidence and falsifying official documents.

The reason for the falsifications? The employee says they were behind on their work and didn’t want to get in trouble for handing in results late.

Chain of custody issues

Fortunately, it seems like, rather than attempting to frame people, the examiner reported negative results. Chief Inspector Inoue Norihiko insists that these forgeries will have minimal impact on dismissed cases. In cases where the examiner reported that they detected no DNA from the suspect, Inoue says that re-tests also came up negative.

Inoue further said that, in cases where the examiner appended data from other cases, their intent was to “make their supervisors’ decision easier,” but that other physical evidence backed up detectives’ overall findings.

However, the mishandling of evidence raises serious questions around how the prefecture handles critical evidence. According to Asahi Shimbun, in 2024, Saga Prefecture conducted 1,233 DNA tests. That’s up from 939 in 2020.

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Legal scholar Tabuchi Kōji told NHK News that he’s “never heard” of a case in which falsified DNA tests went undetected for so long.

“The entire organization lacks a culture focused on raising the credibility of [DNA] testing.”

Sources

佐賀県警の科捜研職員 未実施のDNA鑑定 実施を装う 懲戒免職. NHK News

科捜研のDNA鑑定不正「第三者機関で調査を」 佐賀県弁護士会. Asahi Shimbun

7年間も不適切なDNA鑑定作業 計130件…16件は殺人未遂事件などで証拠として採用 40代職員を懲戒免職 佐賀県警. FNN Prime Online

仕事ぶりよく見せようと…科捜研のずさんなDNA型鑑定、揺らぐ信頼. Asahi Shimbun

AloJapan.com