The Location

The Miyazawas and Yasuko’s relatives lived in two of four homes remaining in a housing development that once numbered in the hundreds. The others had been torn down to make room for the Tokyo Municipal Soshigaya Park; the Miyazawas had sold their home but had not yet moved. In the hopes of attracting potential witnesses, police even released 3D video of the Miyazawas’ house and its vicinity.

Police believe the killer entered the house through the second-floor bathroom and likely left the same way: Its window was open and the screen removed. Rei slept in the adjacent bedroom, which is one reason police suspect he was killed first and strangled instead of stabbed like the others.

Possible Motive

No motive has been established, and none of the theories suggested over the years is particularly convincing.

  • Money: Some of Yasuko’s tutoring money was missing, and there has been speculation that the intruder — possibly a hired killer — might have believed he could somehow access the money the Miyazawas made from selling their house. But the killer did not take all of the family’s cash — close to 250,000 yen (just under $2,000) was found at the scene.

  • Angry skateboarders: I kid you not — police reportedly even investigated whether Mikio’s alleged complaints about the noise from the nearby skate park made someone furious enough to kill his entire family. (Here’s a real headdesk for you: Some have made a gargantuan leap between skateboarders and Drakkar Noir cologne.)

  • Revenge: I’ve only seen this theory espoused by redditors, bloggers, and podcasters, with no factual evidence or insight to support it.

For a detailed examination of the speculation surrounding the killings, check out Faceless, a recent seven-part podcast about the Setagaya family murders. Host Nic Obregón devotes whole episodes to some theories — some sound, others silly — about who the killer might be and his motive for committing the heinous crime.

The Buddha Statue

Police considered it significant that a 2-foot-tall Buddhist statue was found in April 2001 near the Miyazawa house. They distributed more than 30,000 flyers featuring a picture of the statue, a Jizo bodhisattva considered to be a guardian of dead children.

The Reward

There is a reward of 20 million yen (more than $150,000) — the largest in Japanese history — for credible information leading to the arrest of a suspect.

Japan only abolished its statute of limitations for murder in 2010 — otherwise, Miyazawas’ killer might have escaped prosecution if he were caught. Police are still actively investigating the case: More than 280,000 investigators have reportedly worked on it, following up on more than 16,000 tips.

The house where the Miyazawa family was killed is still standing, according to the Faceless podcast, despite the initial plans to demolish it after they moved out. Three years ago, Yasuko’s older sister, Anne Irie, opened the house to reporters. In the video of that tour, you can see dozens of boxes containing the family’s belongings that had been returned by police to the victims’ surviving families. Some of the Miyazawas’ furniture remains, and penciled lines on one wall document the children’s growth. A round plaque with their name surrounded by flowers hangs on the outside wall by the front door.

Source: https://www.buzzfeed.com/drumoorhouse/setagaya-family-murders-unsolved