Lessons from the Zama Killings: Using the Internet to Prevent Suicide


Media reports on how the Zama serial killer used his Twitter account to lure and then murder his suicidal victims have triggered calls for tighter regulations on social networking services. The author believes a much better solution would be to utilize social media more effectively as a suicide-prevention tool.

Shocking Revelations

On October 31, 2017, police arrested 27-year-old Shiraishi Takahiro after a raid of his Zama apartment revealed the dismembered remains of nine victims—all murdered, according to news reports, in just two months between August and October. The revelations shocked the nation not only for the large number of victims but also for how the killer used his Twitter account to identify women with suicidal tendencies and to lure them by offering help in fulfilling their death wish.

I, too, was horrified by the large number of victims but was not surprised to learn that he had used social media to prey on young women. This was not the first time, after all, that people expressing a desire to die online had become embroiled in a crime. Even before the spread of social networking services, killers had identified victims through comments left on suicide websites. Indeed, my doctoral dissertation on using the Internet to prevent suicides was based on interviews with people leaving such comments, including on social media. I was grateful that they took the time to speak at length to me when I was just a graduate student.

Opportunities for Life-Changing Encounters

The government has announced plans to introduce measures designed to prevent a recurrence of the Zama killings. What can the government actually do, though, to achieve its stated goal? My thoughts on this issue, based on my research and personal experience, are as follows.

The first thing to note is that any attempt to regulate the use of social media and other online services by people expressing suicidal tendencies is a nonstarter. It is impossible to prevent people from voicing such ideas, and even if it were, it would be counterproductive. People who tweet their desire to die have been driven to do so by difficult circumstances, and stopping them from posting such tweets will do nothing to remove or mitigate their suffering. What is really needed is to prevent potential assailants from contacting their victims, but that would also be very difficult, since there is no way of identifying would-be offenders before a crime actually takes place.

A more realistic approach would be to design social media sites so that suicidal users are more likely to turn to people offering help, rather than those looking to hurt them. How such sites can be redesigned will depend on the features each site offers, though, so there is no single solution that will work for all.

One promising solution is an online gatekeeping initiative called Yomawari 2.0 launched by Ova—a nonprofit with which I am personally engaged. It uses a Google AdWords function to display an ad for a free, email consultation service every time a user searches a suicide-related term. Those seeking advice are referred to an organization providing face-to-face support (such as a mental health clinic), depending on risk levels and the hardships they face. Ova maintains contact on an ongoing basis with follow-up emails. Initiatives like Yomawari 2.0 can help reduce exposure to sites offering suicide tips and enhance the chances of connecting with assistance groups.

As I mentioned above, this is not a solution that works with all social media platforms. But I believe that the details can be adjusted in line with the features of each site to most effectively reach people in need of help. In fact, social networking services are an effective way of identifying people with suicidal tendencies; my research has shown that people who tweet that they wish to die are at higher risk of suicide than others. Had the victims of the Zama killer seen and taken advantage of the ads for suicide consultation services, there is a chance that the tragedy could have been avoided.

Financial Hurdles

The big challenge is finding a way to finance these operations. Because preventing suicides is not a profitable endeavor, there is little choice but to rely on the government to provide the necessary funds. Whenever horrifying web-related crimes come to light, people are wont to blame the companies providing online services, but those services in themselves are not the problem; Twitter, for example, might be able to offer better features, but it cannot prevent suicidal users from sharing their thoughts online.

And while many people voice the need for measures to prevent a repeat of terrifying incidents like Zama in their wake, few realize that it is ultimately up to them to ensure that such measures are implemented. This is because taxpayers generally do not perceive a need for antisuicide programs, even if they demand a prioritization of crime-prevention funds. Sadly, crimes like Zama will no doubt continue unless the public recognizes that an inclination for suicide lies at the root of the problem.

The Public’s Role

Lastly, I would like to describe a development in which a change in public perception produced tangible improvements in the area of suicide prevention. I am referring to the media treatment of high-profile suicides. In the past, suicides by celebrities or politicians that were given sensational coverage, resulted, for a time, in a large number of copycat suicides—a phenomenon, known as the Werther effect, which has been observed worldwide. In the 1980s, for instance, there was a spike in teenage suicides after Japanese idol Okada Yukiko jumped to her death. Some of the sensational media coverage of the incident can still be viewed today on video-sharing sites like YouTube: images of the singer’s body covered in tarpaulin are accompanied by dark, ominous music, with reporters dashing around the street where the body fell. Today, such media reports would be considered violations of the World Health Organization’s guidelines on responsible reporting, as published in “Preventing Suicides: A Resource for Media Professionals.”

While violations of WHO guidelines still do occasionally occur, Japanese media reports, for the most part, no longer give such melodramatic treatment to suicides today—a marked improvement over the situation some 30 years ago. This is in part thanks to efforts by media organizations to adhere to the guidelines, but perhaps an even bigger factor has been the public’s rejection of sensationalism. News organizations are wont, by nature, to highlight shocking details in the hopes of attracting more readers (pageviews) or a bigger audience. The public must discourage such inclinations by closely monitoring media trends.

Changes for the better may not come about overnight, but shifts in public opinion have had an impact on the media and public policy. If enough people demand that social networking service providers take steps to mitigate the dangers to which suicidal users are exposed, companies will have no choice but to redesign their sites. If the public remains complaisant, on the other hand, so will the service providers. Japan has many population issues and combating suicide seems to be little prioritized, but it should receive more attention. The Zama serial killings should not be treated as mere fodder for tabloid journalism; they should prompt the social media industry to step up its efforts to prevent similar tragedies in the future.

(Originally published in Japanese on November 30, 2017. Banner photo: A policeman stands outside the Zama apartment on October 31 where the dismembered bodies of nine victims were found. © Jiji.)

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