term, literally meaning 'celebrated cause' (don't be confused by the use of the word 'célèbre' - a 'cause célèbre' does not necessarily concern light entertainment stars). A cause célèbre is a righteous crusade which engages the attention of the media - the Dreyfuss affair
is a prime example - and is usually bestowed retrospectively on those causes which are seen to be just; causes which fail to win the approval of the liberal elite
are usually referred to as witch hunts
Thus, when the Guardian highlights the fact that prisons have lockable doors and an intimidating atmosphere, it is a 'cause célèbre', but when the Daily Mail or the Evening Standard run articles on how crime is bad, they are ill-informed reactionary rants. Nowadays the terms seems rather old-fashioned and is more likely to be used bathetically, i.e. accompanying an article on Stella McCartney's attempts to ban dogs from her flat, and so forth.