TOKYO (Kyodo) -- A Japanese court on Tuesday sentenced a man dubbed Japan's "Twitter killer" to death for the 2017 serial murders of nine people who posted suicidal thoughts on social media.
Takahiro Shiraishi, 30, was found guilty in the high-profile case by the Tachikawa branch of the Tokyo District Court of murdering, dismembering and storing the bodies of the nine in his apartment near Tokyo.
Presiding Judge Naokuni Yano ruled that the nine victims did not consent to being killed, and that Shiraishi was mentally fit to be held responsible for the murders.
The judge described the crimes as extremely vicious, adding the case had given people a cause for concern regarding how deeply rooted social media has become in society.
Whether Shiraishi killed the victims with their consent was the major point of contention in the lay judge trial.
Prosecutors had sought the death penalty for Shiraishi, who pleaded guilty to the crimes, but defense lawyers had argued that he was guilty only of the lesser charge of homicide with consent as he had his victims' tacit approval based on messages they sent to him.
While prosecutors pointed out that there was no way the victims consented to being killed based on Shiraishi's testimony that they resisted when being strangled, the defense team argued that they only did so due to their "conditional reflexes." The defense also claimed that Shiraishi was possibly either mentally incompetent or was in a state of diminished capacity at the time of the murders.
But prosecutors concluded he could be held criminally liable after he was put through five months of psychiatric testing before his indictment in September 2018.
According to the indictment, Shiraishi strangled and dismembered eight women and one man aged 15 to 26 from Tokyo and four other prefectures from August to October 2017. He is also alleged to have sexually assaulted all his female victims.
He is believed to have promised to help his victims die via Twitter, using his handle that loosely translates as "hangman," inviting them to his apartment in Zama, Kanagawa Prefecture, after they expressed suicidal thoughts.
Shiraishi said that even if given the death penalty, he would not appeal.
The case has stunned many in Japan, prompting the central government and social networking services to boost support for young people in need of help.
The serial killings first came to light in October 2017 when police officers visited Shiraishi's apartment and found several coolers containing body parts during their search for a missing 23-year-old Tokyo woman, who later turned out to be one of the victims.