OKAYAMA – In what appears to be a first in the judicial system, an Osaka man has been sentenced to hang for killing a woman even though there was only one victim and the perpetrator had no previous criminal record.

Judge Kosuke Morioka of the Okayama District Court, presiding over a panel of professional and lay judges trying Koichi Sumida, 30, said Thursday the victim was also sexually assaulted, making the case “grave.”

Sumida’s lawyer immediately appealed the sentence.

The defendant was convicted of robbing Misa Kato, a 27-year-old temp staff worker and colleague, of around ¥24,000 in cash and personal belongings on Sept. 30, 2011, at a warehouse in the city of Okayama where they worked.

Sumida then assaulted her sexually and stabbed her to death. He dismembered her body and dumped the remains in Osaka.

He was charged with robbery, rape, murder and damaging and dumping a corpse. During the trial he owned up to the charges and said he felt no pity for the victim.

In a Feb. 7 session, however, he apologized in tears to the victim’s family. His lawyer asked for a less severe sentence than death, saying Sumida was repentant.

He is the 16th defendant to be sentenced to death since the lay judge system was introduced in May 2009.

It is the third time the ultimate penalty has been imposed in a case involving only one victim, but in the previous two cases the defendants committed murder within months after leaving prison for previous crimes — one for a murder and the other for robbery resulting in injury.

Lead Judge Morioka said the motive for the crime was to “work off sexual frustration” and “there is little likelihood of rehabilitation.”

Morioka said that it was “not appropriate to consider” Sumida’s lack of a criminal record, given that “the defendant’s inclination toward committing a crime cannot be ruled out.”