Topic I: Approach to Enhancing Investigation Methods and Interrogation

In recent years, police interrogation techniques have been subjected to severe scrutiny due to continued cases resulting in acquittals. Therefore, a variety of approaches to enhancing investigation methods and interrogation have been undertaken to secure the nation’s trust in investigations.

The police are undertaking studies/research and implementing policies to enhance investigation methods and interrogation, as these are both closely linked to public safety. In addition, in order to aid substantiation through objective evidence, police are pressing forward with the use of scientific techniques in investigations as part of the investigation methods enhancement program.

## (1) Study Group for Enhancing Investigation Methods and Interrogation

## 1 ) Reviews undertaken by the Study Group

The “Study Group for Enhancing Investigation Methods and Interrogation” (hereinafter “the study group”), chaired by the chairman of the National Public Safety Commission and comprised of experts, was formed for the purpose of conducting reviews from a wide-ranging perspective over a two-year term in order to ensure the transparency of interrogation without compromising public safety levels.

The study group was convened 23 times from February 2010 to February 2012, to conduct reviews in relation to increasing the transparency of interrogation and enhancing investigation methods in view of the results of studies and research into the stance taken towards investigations and relevant matters in other countries.

A mid-term report, compiled in April 2011, revealed that while countries already implementing transparent interrogation were using a variety of investigation methods not yet in use in Japan, interrogations in Japan, in comparison to other countries, had greater significance and played a greater role in clarifying the truth of cases. The final report compiled in February 2012, stated that the scope of trial-based audiovisual recordings of interrogations should be expanded, and that investigation methods that are highly feasible should be examined promptly toward their adoption and be realized if the methods are considered to be highly effective and their introduction is considered to be appropriate even considering the degree of infringement of human rights.

The study group in session

## Trial-based audiovisual recordings of interrogations by police

## Sep 2008 – Five metropolitan and prefectural police started trial-based recordings

Apr 2009 – All prefectural police started trial-based recordings

O Recordings for confession cases for trial by lay judges in which the offender has been arrested.

Audiovisual recordings of the reading out of the statement

Feb 2010 - Formation of the “Study Group for Enhancing Investigation Methods and Interrogation”

Feb 2012 – Final report given in a session of the study group

## Mar 2012 – NPA established the “Program to Advance Investigation Methods and Interrogations”

For cases to be tried by lay judges, including denial cases audiovisual recordings of a variety of situations such as the recording of statements of defence, etc.

Wide implementation regardless of the type of offense in relation to cases involving suspects with intellectual disabilities