The prosecutors told the Yokohama District Court on Monday that Satoshi Uematsu, a former worker at the Tsukui Yamayuri-en home, was fit to be held criminally responsible at the time of the attack. He is also charged with injuring 26 others in the stabbing rampage at the facility in July 2016. The prosecutors said a psychiatrist's opinion that the defendant's use of marijuana had little or no effect on the attacks is highly reliable. They said Uematsu's belief that it is better to kill disabled people who are incapable of communicating runs counter to social values and there is no room for leniency. The prosecutors also said Uematsu killed defenseless victims one after another in the incomparably cruel attacks.
Source #1: This NHK World News article
During the trial, Uematsu admitted he targeted the victims because he thought he could kill them easily. He said people with severe disabilities have no means of communication.
Source #2: This other NHK World News article
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