Highly qualified, full-time judges, the Law Lords carried out the judicial work of the House of Lords until 30 July 2009. The final appeal hearings and judgments of the House of Lords took place on 30 July 2009. The judicial role of the House of Lords as the highest appeal court in the UK has ended. From 1 October 2009, the Supreme Court of the United Kingdom assumed jurisdiction on points of law for all civil law cases in the UK and all criminal cases in England and Wales and Northern Ireland. As of 30 July 2009, the 12 Lords of Appeal in Ordinary (the Law Lords) were appointed the first justices of the 12-member Supreme Court and were disqualified from sitting or voting in the House of Lords. When they retire from the Supreme Court they can return to the House of Lords as full Members but newly-appointed Justices of the Supreme Court will not have seats in the House of Lords.
Further information on this subject can be found from the following link.
Supreme Court of the United Kingdom