The Diet on Tuesday passed an amendment mandating for the first time the recording of police interrogations as well as changes to the existing wiretap law and the adoption of a plea bargain system, in reforms representing a significant turning point in Japan's criminal justice system.

The measures are an attempt to revamp the nation's notoriously opaque judicial process. Under the new requirements, police and prosecutors will be obliged for the first time to videotape certain criminal interrogations in a bid to prevent the authorities from eliciting coerced confessions.

Investigators have been recording interrogations at their own discretion.