Defense lawyers representing a 34-year-old man accused of stabbing a 11-month-old baby to death at a supermarket in Aichi Prefecture in February argued Thursday that their client should be acquitted, claiming he was insane at the time of the crime.

Katsunao Ujiie, an unemployed man with no fixed address, did not enter a plea at the opening session of his trial at the Nagoya District Court, stating only that he had "left everything up to lawyers."

His lawyers then told the court that Ujiie should be judged innocent because he was mentally incompetent when he stabbed Shoma Aoyama to death with a knife at the Ito-Yokado store in Anjo on Feb. 4.