ABSTRACT

Criminal investigations are obviously ‘something to do with’ the law. But there are many significantly varied ways and different senses in which ‘the law’ (whatever that is taken to mean) can relate to criminal investigations. Before launching into detailed discussion of particular laws and legal doctrines and assessing their practical significance, some of the nuances of this relation should be made explicit. The first part of this chapter therefore clarifies the concept of ‘law’ in its relationships with criminal investigations and supplies some jurisprudential background. The second part presents a critical survey of the police powers most central to criminal investigations and clarifies their basis in law. The third part explores the distinction between ‘police powers’ in legal theory and the realities of investigative practice. It also outlines the legal remedies potentially available to those whose rights have been breached during the course of a criminal investigation. Finally, in conclusion, the last part briefly considers the influence of science and technology on the legal regulation of criminal investigations and the scope for reform.