A 29-year-old Chuo University graduate on Wednesday admitted stabbing a college professor to death last year, but his lawyers said the Tokyo District Court should take into consideration that he has a delusional disorder.
Ryuta Yamamoto stands accused of murdering Hajime Takakubo, 45, a professor in the Faculty of Science and Engineering at the university’s Bunkyo Ward campus, on Jan. 14, 2009. He was stabbed 47 times with hedge trimmers with 27.8-cm blades and bled to death in a men’s room in his office building.
In their opening statement, prosecutors told the lay and professional judges they will not dispute that Yamamoto was of diminished capacity. But they also said that in proving he can be held responsible for the slaying, they will demonstrate he deserves punishment because his intent to kill was self-centered.
The prosecutors said Yamamoto had tried to murder Takakubo on Jan. 13, but put off the slaying until the next day when he realized he did not have a backup plan if the victim tried to defend himself.
After murdering Takakubo, the defendant got worried because a man had seen him exiting the bathroom, the prosecutors said. Yamamoto returned home and threw away the shears and the clothes he was wearing, and also wrote down questions he expected to be asked by police, they said.
During the opening statements, the prosecution and defense both said Yamamoto decided to kill Takakubo because he had believed a group of people led by the professor was constantly watching him and planned to kill him.
Yamamoto’s lawyers said he has been poor at developing positive relations with other people since his early teens and has a tendency to doubt the sincerity of other people’s actions. They said his condition worsened after he entered Chuo University, where he fell behind in his studies and he began to self-inflict cuts on his wrists.
After joining Takakubo’s laboratory in 2003, Yamamoto believed the professor was observing his wrists with suspicion, according to his lawyers.
Yamamoto soon began to believe other students were bugging his house, they said.
After graduating in 2004, Yamamoto’s inability to adjust caused him to change jobs repeatedly, they said, adding he blamed his troubles on what he thought was continuous monitoring by Takakubo’s group wherever he went.
By law, someone deemed to have diminished capacity may face lesser punishment than would otherwise be meted out.
Three men and three women are serving as lay judges in the trial. Together with three professional judges, they will attend four sessions before a ruling is issued Dec. 2.