The law and custom of parliament

The privileges enjoyed form part of the ‘law and custom of parliament’ – lex et consuetudo parliamenti – and, as such, it is for parliament to adjudicate on matters of privilege, not the courts.1 Privileges are embodied in rules of the Houses of Parliament. The United Kingdom Parliament, however, is not free to extend existing privileges by a mere resolution of the House: only statute can create new privileges.2 Privileges derive from practice and tradition; they are thus customary in origin. Nevertheless, they are recognised as having the status of law, being the ‘law and custom of parliament’. Parliament itself can – in the exercise of its sovereign power – place privileges on a statutory basis. For example, in 1770, the Parliamentary Privilege Act withdrew the privilege of freedom from arrest from servants of Members of Parliament. Further, in 1689, Article IX of the Bill of Rights gave statutory recognition to the freedom of speech in parliament. In 1868, parliament ended its own jurisdiction to determine disputed elections, conferring jurisdiction on the courts by way of the Administration of Justice Act.