What was the Setagaya Family Murder?

The Setagaya family murder refers to the unsolved killings of the Miyazawa family—Mikio (44), Yasuko (41), Niina (8), and Rei (6)—in their home in Tokyo's Setagaya Ward on the night of December 30–31, 2000. Despite extensive investigations involving over 280,000 officers and the collection of more than 12,000 pieces of evidence, the perpetrator remains unidentified. Notably, the killer left behind personal items and DNA evidence, suggesting a male of mixed Asian and European descent. https://en.m.wikipedia.org/wiki/Setagaya_family_murder

In 2022, a 7 episode podcast called “Faceless” was released which dove deeply into the Setagaya murder case. It included ample primary sources and research and explored 6 plausible theories surrounding the case. The podcast won the 2023 New York Festivals Radio Awards—Bronze Medal for Best Documentary Podcast and a 2023 Webby’s Best Crime & Justice Podcast Honoree*. In my opinion, the podcast contains some of the most accurate and up to date information on the case. The author, Nic Obregon, spent 2 years researching the case for the podcast, and appears to have remained invested in the case since.

Resolution criteria

This market will resolve to "Yes" if, by December 31, 2030, Tokyo authorities and/or reputable news outlets publicly announce that they have identified the killer responsible for the Setagaya family murders that occurred in Tokyo on December 30–31, 2000. Official announcements from the Tokyo Metropolitan Police Department or reputable news outlets will serve as the basis for resolution. If no such developments occur by the end of 2030, the market will resolve to "No".

Ambiguities

A formal murder charge or conviction is not necessary for a “Yes” resolution as long as there is widespread consensus on the killer’s identity. This could happen if the killer is no longer alive at the time of the announcement, or if the legal process extends past EOY 2030.

There must be a reasonable degree of certainty that the alleged killer actually committed the crime, so persons of interest or suspects may not cut it. For example, if a living suspect is identified but not charged and the investigation is still considered ongoing by EOY 2030, the question will probably resolve “No.”

Significant disputes between reputable sources and the authorities’ official conclusion may result in a “No” or “N/A” resolution but will be handled on a case by case basis.

Considerations

The case has remained unsolved for over two decades, with periodic public appeals for information and a standing reward of 20 million yen for leads resulting in an arrest. Advancements in forensic technology and international cooperation may influence the likelihood of resolution before the end of 2030.

I won’t bet on this market.