Special advocates and amici curiae in national security proceedings in the United Kingdom

This article considers the use of special advocates (SAs) in the United Kingdom in ‘closed material proceedings’ (CMPs) – that is, proceedings where the court relies on evidence that is not shown to one or more of the parties (closed material) in reaching its decision on the substantive issues in the case. It charts the development of CMPs from 1997 to the present day and examines some of the criticisms made of them, including by SAs instructed in them. From the perspective of a barrister with experience of acting in CMPs, this article identifies three particular examples of the difficulties that have arisen in practice in understanding the proper role of SAs and their effect on the way proceedings are conducted by judges: first, the conflict that can arise between the function of acting in the interests of the excluded party (generally, the role of the SA) and that of assisting the court (the traditional role of an amicus curiae); second, whether and to what extent SAs can make CMPs fair; and, third, the extent to which CMPs and SAs should play a part in appellate proceedings.