Contributor(s): Lord Mackay, Ross Cranston | The separation of powers idea is at the heart of all legal democracies. Yet within those democracies there will often be positions of high office which require their holders to perform functions which are both legal and political. In this series of events senior figures who hold or have held positions of this type talk about their lives in the law, the nature of their office, the institutions which they serve, their roles and responsibilities within those institutions, the role of lawyers in government and their understanding of the relationship between law and politics. Ross Cranston is justice of the High Court and visiting professor of law at LSE. Lord Mackay of Clashfern, KT, PC was formerly Lord Advocate of Scotland, 1979-1984 and Lord Chancellor, 1987-1997.