In a discussion about the House of Commons on FLEFO (CompuServe), Mike Ellis mentioned this general brochure (G7), Some Traditions and Customs of the House. It’s an excellent collection of trivia:

bq. In general, the description used is “the Honourable Member for . . .”. However, Privy Councillors (senior Ministers, past or present, and other senior Members) are “the Right Honourable Member for … “. Less frequently heard these days are “the Noble Lord, the Member for … “, which is used for a Member with a courtesy title (e.g. the son of a duke, marquess or earl) who sits in the House of Commons, or an Irish peer, “the Honourable Baronet for … “. Following recommendations made by the Modernisation Committee the House agreed that some of the embellishments which are added to the standard form of address, such as “gallant” (used for Members who have been commissioned officers in the forces) and “learned” (used for Members who are senior barristers) should be abandoned. Often the constituency is omitted, and a Member will be described as “the Honourable Member who spoke last”, “the Right Honourable Lady opposite”, “the Honourable Member below the gangway”, etc. In most cases Hansard will expand these phrases into the form “the Honourable Member for Ockendon (Mr Bloggs)” in order to avoid ambiguity in the printed record of debates. …

bq. Members may speak only if called by the Chair. They are called by name, and must sit down if the Speaker rises to his or her feet (e.g. to call for order, or to interrupt the debate). To catch the Speaker’s eye, Members commonly rise or half-rise from their seats, but if they are not called, they have no redress.

This is some general knowledge that would have helped a German law student whose dissertation I was reading recently. The topic was the change of style in judicial decisions in England, France and Germany. She refers to the form of address in the House of Lords: ‘my noble and learned friend Lord …’, and concludes that this is not a mere convention but shows genuine respect for a fellow-judge – proved by the generally respectful tone:

bq. Dass es sich dabei nicht allein um eine zu bloßer Konvention erstarrte Höflichkeitsfloskel handelt, sondern um einen Ausdruck der tatsächlichen Wertschätzung des Fachkollegen, bezeugt der ganz generell festzustellende respektvolle Umgangston.

(Jutta Lashöfer, Zum Stilwandel in richterlichen Entscheidungen, 1992 ISBN 3-89325-124-3 or 0932-4763 – quite an interesting book).

Of course, noble = a Lord, and learned = a lawyer, so the phrase is absolutely conventional.