One of Japan’s Youngest Serial Killers

He killed his mother and two girls for pleasure.

Some crimes can be prevented, some can not. The murder of a mother by her 16-year-old son might not have been able to be stopped but the murders the boy committed after, could have. Yukio Yamaji, who brutally beat his mother to death with a metal bat was given another chance.

Instead of receiving help from mental health experts, he was let out on the streets to fend for himself. Broke, alone, and with no one to help control his urges and mental illness, he took more lives. Had someone intervened, this boy could have grown into a reformed and rehabilitated man. Instead, he became a serial killer.

This is the story of a boy who killed his mother, then despite confessing and turning himself in, was able to kill again. Why did he kill his mother? Why was he let free after being caught? Who were his next victims? How could this have been prevented?

Yukio

Yukio Yamaji was born on August 21, 1983. He grew up in the city of Yamaguchi in Japan and was an only child. His father died of cirrhosis due to alcoholism when Yuji was only in elementary school. His mother worked as a store clerk. The family was not very well off financially so the death of his father hit both his mother and Yukio pretty hard.

Yukio was also not a very good student. He often kept to himself, rarely talked to other students, especially females, and was known to sometimes lash out violently. Once he even smashed a window at school. He was absent often and after graduating junior high school, he decided to not continue on to high school.

Instead, Yukio got a job delivering newspapers around town. During this time, the Bunshun Newspaper reported that Yukio was seeing an older woman. He had met her at the toy store where he would often go and they began being intimate. However, since Yukio was only a teenager and she was in her 20s, she broke it off. But Yukio wanted to continue seeing her.

Yukio’s mother grew suspicious of Yukio’s relationship and made a call to the woman he was seeing. This enraged Yukio and he decided to take out his rage on his mother.

First Kill

On July 16, 2000, when Yukio was 16 years old he took a metal baseball bat and battered his mother to death. Yukio told investigators he took the bat and hit her on the head, also breaking some glass. After he hit his mother, she was walking over the shards of glass trying to steady herself. Yukio kept on hitting her and couldn’t recall how many times or how long the attack lasted. His mother had multiple fractured ribs and she was beaten so bad, her face was indistinguishable.

Days after he killed his mother he called and invited the woman he was seeing to his house for lunch. During lunch, he kept asking her if she could smell blood. The woman finding his mother’s dead body called the police.

Arrest & Sentencing

Yukio was arrested, tried in family court, and sentenced to juvenile detention. Because he was a minor, this was his first offense, and he had confessed to killing his mother, the courts believed he could be rehabilitated.

He told police and the courts that he decided to kill his mother because she kept spending too much money, accumulated a huge amount of debt, and because she called the woman he was seeing and tried to end their relationship.

The court felt that Yukio didn’t plan the murder initially so sent him to a reform center for troubled minors. But after just three years he was found to be “mentally repaired” and was granted parole in 2003.

Released & Lost

Since both of Yukio’s parents were now deceased, he was out on his own. He lived with his grandmother but quickly left to be out on his own. After being released from the reform center, he was hoping to meet with the woman he was previously dating. He told staff, “There is a woman waiting for me once I leave here.” But once released he couldn’t get in contact with her.

He moved to a different city and found a job at a pachinko parlor, which are gambling centers similar to slot machines. He would return to his hometown on holidays to look for the woman but could never find her. He was also reported as stealing coins from various pachinko parlors around town.

He ended up becoming friends with some other thieves at the pachinko parlor and would travel around Japan with them. One of his associates talked about their visit to Fukuoka at a hostess club. Hostess clubs are where men go after work to drink and socialize while beautiful women in fancy gowns pour drinks and sit with the men. At the hostess club, the acquaintance recalled, “I didn’t really enjoy going out with him. Even at the hostess clubs, he was too shy to talk to the women.”

Hanging around with people who weren’t really his friends, having no fixed permanent address, and still having trouble socializing with women, Yukio’s frustration and urges continued to grow.

The Sisters

Yukio ended up finding a place to live in an area of Osaka in a condominium block. In that same condominium, block resided two sisters named Asuka and Chihiro Uehara. Although they didn’t know Yukio, he had become captivated by them, especially Asuka.

According to Yukio’s confession, he targeted Asuka because she looked like the woman he used to date. Yukio would sometimes follow her and found out which unit she lived in. He then messed with her unit’s power and caused a power outage. On November 16th, Yukio tried to find out if there were any other people living in the apartment besides the sisters and broke into her unit. No one was home.

The next day after she came home from work, he ambushed Asuka in the apartment. Then when Chihiro came home, he attacked her as well. Using a butcher knife he stabbed both girls in the face and chest and sexually assaulted them. Yukio explained his feelings when he began the attack,

“When I pulled the knife out of one sister’s chest, I saw her leaning back and my excitement became extreme and I got a complete erection. I cut her hand with a knife to increase my sexual arousal, I stabbed her right breast with a knife.”

It was reported that Yukio was ejaculating while killing the two girls. He also remembered ejaculating while killing his mother as well. After raping and murdering both sisters, he smoked a cigarette on the balcony, stole 5000 yen (about $50) that he found in the apartment as well as Atsuko’s favorite lighter. He set fire to the room and left.

Firefighters found the two sisters in the apartment and a homicide investigation began. Quickly, on December 5th, Yukio was brought in for questioning and he confessed to raping and killing both girls. He told police,

“The reason I killed them was because I had a lot of fun and I couldn’t forget when I killed my mother a long time ago, so I decided to kill again and killed them. The target could have beeen anyone, not just these two.”

He also added, “I wanted to see blood.”

Yukio was willing to talk to police and prosecutors because the prosecutor was a beautiful woman. He explained the rape, the murders, and his motives willingly. He also told them the location of the murder weapon. After killing the girls, he had buried the knife in a shrine nearby.

Arrest & Sentencing

Yukio was charged with double homicide and the prosecution had a lot of incriminating evidence on him. Along with his confession and description of the crime and details regarding the location of the murder weapon, he also had Asuko’s lighter which helped connect him to the fire and being in the women's apartment as well.

The prosecution along with the confession told the story of Yukio committing a “lust murder” and gaining pleasure from the murders he committed. They wanted the death penalty and Yukio was quite helpful in proving their point. He told the court that he would most probably kill again if released back into society. He also didn’t show any regret or remorse for killing either his mother or the sisters.

Yukio’s defense team argued that he could not differentiate between right and wrong when he committed the crime and felt he wasn’t competent enough to stand trial. They also ordered that Yukio have a full psychiatric evaluation to understand the extent of his mental illness. After the evaluation, the defense informed the court that Yukio suffered from Asperger Syndrome and stated he was unfit to stand trial.

However, the judge sided with the prosecutors who insisted Yukio was mentally competent and the trial continued. In May 2006, Yukio pleaded guilty to the murder of the two sisters. Both Yukio and his defense team seemed to be expecting the death penalty as Yukio himself said, “Obviously, I will be sentenced to death… I am not afraid of death,” and his defense team added, “He has no desire to live and his feelings do not extend to the life of another person, either. It will probably be impossible for him to sincerely repent from the bottom of his heart.”

The judge sentenced Yukio to death saying,

“The defendant is demonically possessed with killing people… The victims were killed amid unimaginable fear and pain, and it is inevitable to hand down capital punishment.”

The judge felt that if Yukio had felt remorse or apologized for his crimes, he might have been given a more lenient sentence. Instead, Yukio was executed in 2009 at age 25. He was the youngest person to be executed since 1972.

It seems that Yukio had lost all will to live and felt that he would never be rehabilitated. His actions and presentation in court seemed like he was committing suicide by execution. He did not apologize, show remorse, or even seem like he wanted another chance at life. His upbringing, death of his father, murdering of his mother, and loss of the woman he was in love with, was all too much for Yukio to deal with.

This case and Yukio’s life, in general, was all about the failures of society and lack of support for those suffering from mental illness. Especially those who are not financially well off. Even in Japan, which is a modernized and wealthy country, some people live in poverty and can’t receive the financial and mental support they need.

Had there been some system in place after Yukio’s father died, that could help support a mother and a boy suffering from mental illness, maybe Yukio wouldn’t have murdered his mother. Had the school done more when they noticed his behavior or the government intervened when Yukio didn’t go to high school, Yukio might have been able to live a normal life. Unfortunately, he became one of the youngest serial killers in Japanese history to be executed.

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