Working peers

In the United Kingdom, life peers are appointed members of the peerage whose titles cannot be inherited, in contrast to hereditary peers. In modern times, life peerages, always created at the rank of baron, are created under the Life Peerages Act 1958 and entitle the holders to seats in the House of Lords, presuming they meet qualifications such as age and citizenship. The legitimate children of a life peer enjoy the rank and style of children of hereditary peers, being entitled to style themselves with the prefix "The Honourable," although they cannot inherit the peerage itself.

The Crown, as fount of honour, has the undoubted right to create peerages, whether hereditary or for life. In the early days of the peerage, the Sovereign had the right to summon individuals to one Parliament without being bound to summon them again. Over time, it was established that once summoned, a peer would have to be summoned for the remainder of his life, and later, that the peer's heirs and successors would also be summoned, thereby firmly entrenching the hereditary principle.

Nevertheless, life peerages lingered. From the reign of James I to that of George II (between 1603–1760), 18 life peerages were created for women. Women, however, were excluded from sitting in the House of Lords, so it was unclear whether or not a life peerage would entitle a man to do the same. For over four centuries—if one excludes those who sat in Cromwell's House of Lords (or Other House) during the Interregnum—no man had claimed a seat in the Lords by virtue of a life peerage. In 1856, it was thought necessary to add a peer learned in law to the House of Lords (which was the final court of appeal), without allowing the peer's heirs to sit in the House and swell its numbers. Sir James Parke, a Baron (judge) of the Exchequer, was created Baron Wensleydale for life, but the House of Lords concluded that the peerage did not entitle him to sit in the House of Lords. Lord Wensleydale was therefore appointed a hereditary peer. (In the event, he had no sons, so his peerage did not pass to an heir.) (See also Wensleydale Peerage Case (1856).)

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