The Government has previously rejected calls for the introduction of DCRs, partly due to a lack of research. However, much more evidence now exists, from projects around the world. The IWG was set up to take an objective look at this growing evidence and to consider whether DCRs would have a significant impact on the particular problems in the UK. Chaired by Dame Ruth Runciman, the IWG included senior police officers, academics, health professionals and a practising barrister. Over a 20-month period, the IWG reviewed published evidence, commissioned new research, heard from relevant witnesses and visited DCRs abroad.