Must politicians live in their constituencies?

Do you have to live in a place to represent it? Should you have lived there for some time? Been born there? These are some of the questions raised by a court ruling that Rahm Emanuel, a native Chicagoan, cannot run for mayor of his home town, as he's lived in Washington DC for the past two years. What he was doing there, of course, was serving as Barack Obama's chief of staff, though this didn't do him any favours with the authorities in his home town. Do you think the ruling is fair? Should prospective MPs in the UK, for example, be required to live in the constituency they plan to represent for a certain period? At the very least it might help them avoid gaffes such as Liverpool MP Luciana Berger's failure to recognise Bill Shankly . If you're not in the UK, what are the rules where you live? Do you think they should be changed?