Japan Resumes Executions, Executes ‘Twitter Killer’ Responsible for Nine Murders

Japan has carried out the execution of Takahiro Shiraishi, infamously known as the “Twitter Killer,” marking the country's first use of capital punishment since 2022. Shiraishi, who was convicted of murdering and dismembering nine individuals he met through Twitter in 2017, was hanged after years of legal proceedings, psychiatric evaluations, and intense public debate. His execution has reignited conversation around Japan’s use of the death penalty and the dark intersection of social media and crime.

This article examines the case, the public reaction, and what the execution signals about Japan’s justice system and its stance on capital punishment.

1. The Crimes That Shocked Japan

Takahiro Shiraishi was arrested in October 2017 after police found dismembered body parts in coolers inside his Tokyo apartment. His victims—eight women and one man—were all between the ages of 15 and 26. He had approached them on Twitter, using hashtags related to suicide, offering help to those considering taking their lives. Shiraishi claimed to sympathize, but he had darker motives.

Once he gained their trust and lured them to his apartment, he would strangle the victims and dismember their bodies, storing the remains in iceboxes and toolboxes. He admitted to his crimes during interrogation, describing his actions in chilling detail and expressing no remorse.

The case drew immediate and widespread attention in Japan and abroad. What made the murders especially disturbing was the methodical use of social media to identify and manipulate vulnerable people, making it one of the most horrifying modern serial killings in Japan’s history.

2. The Trial and Sentencing

Despite initially expressing a willingness to accept his fate, Shiraishi's defense team at trial attempted to argue diminished responsibility, suggesting he suffered from mental illness that impaired his judgment. However, psychiatric evaluations found him fit to stand trial.

In December 2020, the Tokyo District Court sentenced him to death, rejecting the defense's claims of mental incompetence. The judge concluded that Shiraishi was fully aware of his actions and acted deliberately for sexual and personal gratification, not from psychological disturbance.

The trial offered painful testimony from the families of the victims, many of whom had no idea their loved ones were considering suicide or in contact with Shiraishi online. The court's verdict was met with relief by the victims’ families and the general public, many of whom supported the use of capital punishment in this case.

3. Japan’s Death Penalty: A Controversial System

Japan is one of the few developed countries that retains and actively uses the death penalty. Hanging is the sole method of execution, and prisoners often receive little to no notice before their execution is carried out. The practice has been criticized internationally for its secrecy and psychological toll on inmates.

Japan’s government defends capital punishment as necessary for the most heinous crimes and as a deterrent. Public support for the death penalty remains high, with over 80% of Japanese citizens in favor, according to national surveys.

However, Japan typically uses the death penalty sparingly. Executions are rare and usually occur without public announcements beforehand. The last execution before Shiraishi’s was in 2022, and prior to that, in 2019, Japan executed multiple members of the Aum Shinrikyo cult responsible for the 1995 Tokyo subway sarin gas attack.

Shiraishi’s execution marks a resumption of capital punishment in Japan after a relatively long pause, suggesting the state still sees the death penalty as a necessary instrument in extreme cases.

4. The Role of Social Media in the Crimes

One of the most alarming aspects of the case was how social media enabled the killer. Shiraishi used Twitter to search for users expressing suicidal thoughts, then offered to help them die "together" or offered sympathy and companionship. His messages targeted emotionally vulnerable individuals, and in several cases, he visited victims multiple times online before luring them to his apartment.

The case raised urgent questions about:

• The responsibility of platforms like Twitter to monitor harmful content

• The ease of online manipulation, especially for young users dealing with mental health challenges

• The legal limitations surrounding digital communication and predatory behavior

In response to the public outcry, Japanese lawmakers and social media companies began re-examining policies around suicide-related content. Twitter implemented some changes, including directing users to suicide prevention resources when certain keywords were searched.

5. Public Reaction to the Execution

Reactions to Shiraishi's execution have been largely supportive across Japan. Many see it as a form of justice for the nine victims and their families. On social media, hashtags related to his case trended again, with users expressing both horror at his crimes and relief that he had finally been punished.

At the same time, some human rights advocates voiced concerns. International watchdogs like Amnesty International condemned the execution, stating that capital punishment should be abolished entirely, regardless of the crime. They criticized Japan’s execution procedures and called for transparency in the legal process.

However, these views remain in the minority within Japan. For most citizens, especially the bereaved families, the execution brought a sense of closure, albeit painful.

6. Legal and Ethical Reflections

The “Twitter Killer” case has become a reference point in debates around:

• Ethics of the death penalty

• Mental health and criminal responsibility

• Digital safety and suicide prevention

It has prompted discussion in Japan's legal circles about whether existing laws are sufficient to prevent similar crimes and whether capital punishment truly acts as a deterrent or merely satisfies societal demands for retribution.

Legal experts point out that while the punishment fits the gravity of the crime in this case, preventive measures—like mental health awareness, online content monitoring, and early intervention—are more crucial in reducing such tragedies.

7. A Tragic Reminder and a Cautionary Tale

The case of Takahiro Shiraishi is a harrowing reminder of how modern technology, when misused, can lead to devastating outcomes. It also highlights the emotional isolation and psychological pain faced by young people in Japan and around the world—many of whom turn to social media in search of comfort or community.

The victims of this case were not just statistics—they were individuals with dreams, families, and futures. Their lives were tragically cut short by someone who exploited their vulnerabilities for his own gratification.

As Japan moves forward, the hope is that this tragic chapter will lead to tighter safeguards, increased digital literacy, and greater empathy in both law and society.

With the execution of Takahiro Shiraishi, Japan closes one of its most disturbing modern criminal cases. The “Twitter Killer,” who turned social media into a hunting ground, has met a fate many saw as just. But the deeper issues—mental health, online exploitation, and justice reform—remain unresolved.

This execution may offer closure, but it also serves as a stark warning: Technology, while empowering, can be weaponized in the wrong hands. The challenge for Japan and the world is to ensure that the tools we use to connect don’t become instruments of manipulation, and that justice continues to evolve in both fairness and humanity.