Senior Law Lord

Lords of Appeal in Ordinary, commonly known as Law Lords, were appointed under the Appellate Jurisdiction Act 1876 to the House of Lords of the United Kingdom in order to exercise its judicial functions, which included acting as the highest court of appeal for most domestic matters. The House of Lords, however, lost its judicial functions upon the establishment of the Supreme Court of the United Kingdom in October 2009; those in office became Justices of the Supreme Court of the United Kingdom, and those Supreme Court justices that have seats in the House of Lords lost their right to speak and vote there until their retirement as justices of the new court.

To be appointed a Lord of Appeal in Ordinary under the 1876 Act, an individual was required to have been a practising barrister for a period of fifteen years or to have held a high judicial office — Lord Chancellor (before 2005) or judge of the Court of Appeal, High Court or Court of Session—for a period of two years. Lords of Appeal in Ordinary were required to retire from judicial office at 70 or 75 years of age, though as peers under the style of Baron they continued to serve as members of the House of Lords in its legislative capacity for life.

Lords of Appeal in Ordinary were occasionally joined by other Lords of Appeal in exercising the judicial functions of the House of Lords. Lords of Appeal included holders or former holders of high judicial office who were members of the House of Lords, but not by virtue of the Appellate Jurisdiction Act (e.g. life peers under the Life Peerages Act 1958). The Lords of Appeal continue to hold the style for life.

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