An old method is hypnosis, in which the witness is put to a trance and then asked to re-experience the incident. Typically, witnesses under hypnosis can tell more details about the incident and with greater confidence. It became very popular in the 1980s. However, scientists have since discovered that the 'memories' recalled during hypnosis were commonly constructed under leading questions and can seriously mislead the investigation. Today, very few courts admit witness testimonies under hypnosis.

Scientists and investigators now know that good rapport with the witness and strategic questioning are the two most important factors in helping the witness recall accurate details of an incident. New memory-enhancing methods have been scientifically proven to be more effective than traditional Q&A interviewing. One approach is Cognitive Interviewing (CI), in which the witness is put in a relaxed atmosphere and the interviewer follows a logical step-by-step recall approach. Essentially, the witness is supported in recalling the incident freely without interruption, and when finished, the interviewer helps the witness break down the memory into segments from which further details can be recalled 'frame-by-frame'. CI also treasures information that seems irrelevant now but can be very useful in future. CI has been successfully adapted for video-recorded interviewing with child witnesses.

So, next time when you conduct an interview with key witnesses, will you find an undisturbed supportive environment to facilitate free-narration and then help the witness recall details segment-by-segment? If you do, you will find richer and more accurate details in the statement obtained.

For further information about forensic and criminal psychological competency, you can contact the Police Clinical Psychologist of Child Protection Policy Unit at 2804-1437.

Stress management workshops

The PSG is organising a series of stress management workshops to be conducted in Chinese. The next one is at the Police Sports & Recreation Club Art Room on January 18 from 8.45 am to 12.30 pm but participants are required to arrive 15 minutes before the programme starts. Thirty places for each session will be allocated on a first-come-first-served basis. To make a reservation contact PSG on 2866-6207.

Seek advice and help from the Psychological Services Group: PHQ, Hong Kong Island and Marine: 2866-6206 ( 5/F, 111 Leighton Road, Causeway Bay ); Kowloon and the New Territories: 2735-3739 ( 22/F, Ocean Building, 80 Shanghai Street, Kowloon ). PEN: psg@police.gov.hk