The Utsunomiya District Court on Wednesday began a retrial of Mr. Toshikazu Sugaya, who had served 17 1/2 years of a life sentence in prison for killing a child until he was released in June on the strength of a new DNA test.

Merely restoring Mr. Sugaya's honor, however, should not be the sole purpose of the retrial. The court should also strive to clarify all mistakes made by the police, prosecutors and the court during the life of this case.

Told the results of a DNA test in December 1991, Mr. Sugaya confessed to the 1990 murder of a 4-year-old girl in Ashikaga, Tochigi Prefecture, and was arrested. But it is now clear that the original DNA test was flawed. The court should find out why the investigators put so much faith in the reliability of that test.