Prime Minister of the United Kingdom the convention developed that the Prime Minister should always sit in the lower house. As leader of the House of Commons, the Prime Minister's authority was further enhanced by the Parliament Act of 1911 which marginalised the influence of the House of Lords in the law-making process. The Prime Minister is "ex officio" also First Lord of the Treasury and Minister for the Civil Service. Certain privileges, such as residency of 10 Downing Street, are accorded to Prime Ministers by virtue of their position as First Lord of the Treasury. The status of the position as Prime Minister means that
Council of Civil Service Unions v Minister for the Civil Service the determination of national security issues is an executive function and it would be inappropriate for the courts to intervene. The House of Lords held the Royal Prerogative was subject to judicial review, just like statutory instruments. However, on national security grounds, the action of restricting the trade union was justified. Lords Fraser, Scarman and Diplock all believed that the issue of national security was outside the remit of the courts. Lord Diplock wrote "it is par excellence a non-justiciable question. The judicial process is totally inept to deal with the sort of problems which it involves." Lord Fraser stated