Japan's retrial system will be scrutinised by legal experts for possible revision, officials said Friday, following last year's acquittal of the world's longest-serving death row prisoner.

Critics of the retrial law say the system does not offer sufficient safeguards to victims of wrongful convictions because of its arduous process that can take decades.

The system -- so time-consuming that campaigners call it the "Door That Never Opens" -- has not been changed since it was introduced over 70 years ago.

It follows the landmark acquittal of Iwao Hakamada, 88, who was found innocent in September of a 1966 quadruple murder for which he spent over four decades in confinement, mostly on death row.

Hakamada is only the fifth death row inmate granted a retrial in Japan's post-war history. All four previous cases resulted in exonerations.

But it took him 42 years to have his case reopened in total, delayed by snail-paced deliberations on his application and repeated appeals by the prosecution.

Now the justice ministry will ask a panel of legal experts to discuss revising the system, minister Keisuke Suzuki told reporters Friday.

Discussions by the ministry's legislative council can start as soon as this spring, local media reported.

"We will consult the council as soon as all preparations are made," a justice ministry official told AFP.

AFP

Hideo Yamada (left), chief prosecutor of the Shizuoka District Public Prosecutors Office, bows to apologise to Iwao Hakamada (2nd right) after his acquittal was confirmed in a retrial on Nov 27, 2024. (File photo: AFP/Jiji Press/Japan Pool)

Japan retrial system to be reviewed after landmark acquittal