The Otsu Family Court on Wednesday ordered a 15-year-old boy accused of killing a 16-year-old in March to undergo rehabilitation at a reformatory.

The court determined the boy, whose name was withheld under the Juvenile Law, and another 17-year-old youth beat Yu Aoki, who had a physical disability, at an elementary school in the city of Otsu on Mar. 31, resulting in the death of the victim six days later.

In handing down the ruling, the court said the teen needed to undergo reformatory education for a long period of time, because he believes violence "is an effective tool for self-expression and solving problems."

Citing that the youth's 90-minute beating of Aoki was "intense and one-sided," the court said the deed was very malicious. During the court hearing, the victim's mother, Kazuyo, 52, was allowed to speak out about her son's death.

A lawyer representing her said it was the first juvenile case in which a member of a victim's family offered such testimony after amendments to the Juvenile Law, which took effect April 1, allowed such a procedure.

The family court inquiry of the other boy in the assault is pending.