Serial killer prompts Japan, and Twitter, to mull over online rules

The suspect, Takahiro Shiraishi (centre), dubbed the "Twitter killer", reportedly lured his victims - aged between 15 and 26 - by trawling social media, and the gruesome discovery has prompted the government to consider tightening internet regulations to restrict suicidal posts. PHOTO: AFP

TOKYO (BLOOMBERG) - A Japanese serial killer's alleged use of Twitter to lure victims to his apartment has prompted the government and the social media platform to look at how the tool is regulated in the country.

Police arrested a 27-year-old man after saying that they found nine dismembered corpses at his home in Zama, about 40km south-west of Tokyo. He lured his victims using hashtags aimed at people tweeting about wanting to commit suicide.

Takahiro Shiraishi has admitted killing all nine people - including a girl as young as 15, according to local media.

Chief Cabinet Secretary Yoshihide Suga said last week the government will convene a special committee to create a plan to prevent recurrences by year end.

The government last year revised an anti-stalking law to include social media posts after a young woman was attacked by a knife-wielding assailant who had threatened her on Twitter.

Twitter's chief executive Jack Dorsey commented on the case during a visit to Tokyo this week. "It's very unfortunate, it's extremely sad. We need to take our responsibility and make sure that our tool is being used in positive and healthy ways," he said in an interview with NHK on Wednesday (Nov 15).

He also noted the difficulties in completely eradicating all harmful tweets related to suicide, but he hoped Twitter could become a tool for prevention.

A spokesman for Twitter's Japan operations said the company frequently communicates with the police and other agencies, and plans to continue the discussion on safety.

Earlier this month, the company clarified guidelines on what posts are permissible under Twitter rules, specifying that any posts that encourage or promote suicide and self-harm are against company policy.

Professor Kaori Hayashi of the University of Tokyo said Japan has long neglected the debate on how freedom of expression ties in with social media.

While the government may ask companies like Twitter and Facebook to impose some restrictions on language, Prof Hayashi said it's unrealistic to directly regulate them. "You can't just turn off the faucet on speech," she said.

According to a recent NHK survey, 68 per cent of respondents said they believe measures are needed to restrict suicidal posts on social media.

Japan's suicide mortality rate is the sixth highest in the world, with a recent government report saying it is the leading cause of death in the country among 15 to 39 year olds, reported NHK.

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