The prosecution system in England and Wales has been accused of having a high acquittal rate because weak cases are pushed to trial by the police. This study found that varying legal powers allow the police to press a case in court against the prosecutors' advice. In England, the police view their responsibility as continuing until conviction. The formal structures of arrest, summons, and charge limit prosecuting solicitors' opportunities to examine cases yearly in the process, and the law rests ultimate authority to drop cases with the chief constable. Although recent recommendations would give prosecutors the formal power to terminate prosecutions, this study demonstrates the likelihood that the police will still control the early stages of case assessment and that weak cases will continue to be forwarded for trial. Study data, footnotes and endnotes, and 26 references are included. (Author abstract modified)