Tuesday's ruling in which a 27-year-old man was sentenced to death for the 1999 murders of a mother and her infant daughter in Yamaguchi Prefecture marks a major judicial change, according to legal experts.

The Hiroshima High Court handed down the death penalty to the defendant, reversing its earlier ruling of life imprisonment made in 2002. The retrial took place following an order by the Supreme Court in 2006 that the high court revisit the case with a mind to meting out capital punishment.

"This ruling has a significant meaning (to judge whether the death penalty should be imposed on juvenile perpetrators) and sets a new precedent," said Hidemichi Morosawa, a professor of criminal law and victimology at Tokiwa University in Ibaraki Prefecture.