It's a term the British press has for when they do the full "destroy this person" 24/7 coverage of someone over some often minor scandal. To monster someone. It isn't good, but they're self-aware enough to know they're doing it. It's very wrong to have high opinions of the British press generally - including the BBC (domestic) these days - but they are at least not as full of shit about the role they actually play, which is not merely as objectitudinal impartial observers just presenting the facts and occasionally calling balls and strikes.
