AN independent team should investigate whether Hong Kong prison guards are sharing power with select inmates, a provisional legislator has said. 'There is something wrong with the system and we need more independent studies,' independent Dominic Chan Choi-hi told a security panel meeting. His call followed an internal inquiry by the Correctional Services Department, which concluded the 'B chai system' was no longer operating in prisons. The investigation was launched after three B chais, or favoured prisoners, led a fatal attack on another prisoner who flouted their authority. The victim's screams drew a Lai Chi Kok duty guard to the scene, but he was said to have left when two B Chais told him nothing was wrong. The CSD's internal inquiry concluded its staff had not been negligent in their duties. 'What sort of measures are in place to prevent a recurrence?' Mr Chan asked CSD assistant commissioner Kelvin Pang Sung-yuen. 'I think this is just the tip of the iceberg.' Democratic Alliance for the Betterment of Hong Kong legislator Lau Kong-wah wanted to know whether high-ranking triad prisoners were being allowed special status within prison walls. But Mr Pang said CSD staff would never rely on 'networks among the inmates themselves'. 'We won't allow prisoners to manage prisoners and that has never been done,' he said. If CSD officers were caught sharing power with prisoners, the department 'would impose the necessary disciplinary sanctions', he added. The department had 'learned a lesson from this incident' and was launching a special staff training programme as a 'preventative measure to prevent a recurrence'. The programme will target enhanced awareness, assertiveness training and stress management. Earlier this year, three B chais were found guilty of manslaughter and six other inmates convicted of assault occasioning actual bodily harm on a fellow inmate who was beaten to death. Wong Hing-kwok, 27, was killed on April 28 last year after he ignored a B chai who had scolded him for not sweeping the floor properly.