Kyoto Police Question Claims of Poor Planning in Yuki Adachi Case, Pointing to Possible Impulsiveness

Is this a spontaneous crime?
Questions remain over how much of the testimony of Adachi Yuuki (37), the stepfather arrested on suspicion of abandoning the body of Yuki Adachi (11) in a mountainous area in Sonobe-cho, Nantan City, Kyoto Prefecture, can be believed.
The charge against him is that, between the morning of March 23 and around 4:45 p.m. on April 13, he transported and concealed the body of Yuki in a forested area in Sonobe-cho, Nantan City, Kyoto Prefecture, thereby abandoning it. In response to police questioning, Adachi reportedly said:
“There is no mistake in what I did.”
He is also said to have made statements regarding the killing of Yuki.
According to a police source interviewed by this site:
“During interrogation, Adachi does not become agitated and speaks about the incident in a calm, matter-of-fact manner. Investigators are carefully working to verify whether there are inconsistencies between his statements and the actual circumstances.”
Recent investigations have revealed that the body was temporarily left in a toilet near an elementary school. It is believed that he struggled with how to handle the remains and may have moved them to several other locations.
Given this, some view it as:
a disorganized, opportunistic crime
However,
A social affairs reporter for a national newspaper points out:
“The body was not buried out of fear of discovery, and the methods were undeniably sloppy. However, it is too early to conclude that this was a spontaneous crime.”
Adachi is also reported to have stated regarding the killing method:
“I impulsively strangled him.”
This constitutes strangulation, which in criminal trials is often judged as intent to kill.
When a person is strangled with bare hands rather than a rope or cord, it typically takes time to inflict fatal damage. In many cases, if there is no intent to kill, the perpetrator would regain composure during that time and ease their grip.
The aforementioned police source commented:
“The fact that strangulation was carried out to completion will likely be interpreted as indicating clear intent to kill. The authorities are proceeding with an investigation with murder charges in mind.”
Additionally, an autopsy found no knife wounds on the body, and the cause of death is currently listed as undetermined.
The suspect, who was a non-family outsider within the Adachi household
While some media reports describe the case as lacking planning, police are said to hold a different view.
Yuki’s elementary school was about 9 km from his home, and he normally commuted by school bus, seen off by his grandmother. However, on the day of the incident, March 23, only that day, his father decided to drive him to school.
In voluntary questioning before his arrest, Yuuki Adachi is said to have stated:
“I drove my son to elementary school, but then took him to another location within the city and killed him.”
There is a possibility that some kind of trouble occurred in the car, leading to a sudden change of destination. However, the fact that a specific other location is mentioned suggests that it may not have been purely impulsive.
Adachi married Yuki’s mother last December after meeting her through work. He moved into the “Adachi household,” where four generations lived together: the great-grandmother, grandmother, Yuki’s mother, and her brother’s family. His relationship with Yuki was by no means good, and some reports say Yuki once said:
“I can’t stand having some weird guy in the house.”
It is also said that he refused to talk about his stepfather at school.
According to a police source:
“At the time, Yuki was in the fifth grade and at a sensitive age. It would not be surprising if he developed feelings of rejection toward his stepfather. On the other hand, the suspect, who had entered the Adachi family as an unusual case of a live-in son-in-law, was essentially an outsider. With his wife present, it would have been difficult for him to act aggressively inside the home. It is possible that the only place he could have taken out hostility toward Yuki was outside the Adachi household. We are currently continuing a careful investigation, including the issue of planning.”
Whether it was a spontaneous act or something else—the prefectural police are not simply accepting the suspect’s statements at face value and are examining the case from multiple angles.
Interview and text by: Norifumi Arakida (FRIDAY Digital Entertainment Desk)