His report finds that a series of brutal acts by members of British forces led directly to the death of Baha Mousa; others were involved in assaulting him and his fellow detainees.
It also finds that others who could have intervened to prevent it failed to do so, and it reveals that there were inadequate doctrines and procedures in place for prisoner handling at the time.
Sir William makes a large number of recommendations on doctrine, training and practice in relation to prisoner handling designed to ensure that such an incident never happens again.
Defence Secretary Dr Liam Fox has accepted all of the recommendations in principle, except one on techniques used during tactical questioning.
The evidence from the inquiry will now be reviewed by the Iraq Historic Allegations Team to establish whether there needs to be further investigation of the role of any of those concerned.
Published 8 September 2011