This thesis is an account of the campaign to abolish the death penalty for murder in Britain from the mid 1950s to the late 1960s. It examines the campaign and the debate that it generated from a very broad perspective. It looks briefly at the history of capital punishment in this country so as to set the campaign in context. It focuses on the chief pressure group set up to lobby for abolition, the National Campaign for the Abolition of Capital Punishment (NCACP), and examines in detail its motivation, activities, strategy and influence. It examines the high politics of the campaign; the role played by government and opposition and the interplay between them, and scrutinizes the Parliamentary debates. It examines the role of the main political parties and their internal conflicts, both structurally between front bench, backbench and grassroots membership, and ideologically between pro and anti-hangers and examines the way in which the configuration of opinion within the parties affected the controversy. It looks at the debate within the framework of the other 'conscience' issue campaigns of the time in order to see what light this casts upon the process of pressure group activity and policy change.