Graham Linehan (co-creator of such beloved TV as Father Ted and The IT Crowd) asked Channel 4 why they hadn't aired the most recent Daily Show in the UK, given that the episode deals with the News of the World scandal. The answer he got floored him: as it is against the law in the UK to use Parliamentary footage for satirical purposes, the Daily Show episode in question couldn't be aired here.
The issue is Parliamentary Copyright, a weird concept in UK law that gives Parliament (not the public) ownership over its publications, utterances, and so on. Parliamentary copyright means that it's illegal to print books containing complete records of Parliament without Parliament's permission (contrast this with the US, where anything produced by the federal government is presumptively in the public domain, belonging to all people).
We tend to think of Parliamentary Copyright as a kind of innocuous peccadillo — after all, the Clerk of Parliament gave a license (retroactively) to the activists who made They Work For You, the best-of-breed Parliamentary tracker and activist tool. But this shows what happens when politicians, and not the people, own the record of government: Britons are denied access to commentary on their national news because there's no way an American TV show will know or care enough about Parliamentary Copyright to get a license to use clips in its shows in case the shows are exported to the UK.