Is there a danger, perhaps - or, more accurately, a flaw - in the assumptions we're taught to have about certain types of crime or mystery? For example, there are numerous clichés in many ghost stories; simply because those clichés are effective and because we often relish them. But this may be limiting for creator and audience and is arguably stale thinking...
Sometimes, it's also classist, by mistake or design: just as we might enjoy the trappings of a Victorian ghost tale or a real-life crime story, that created atmosphere is dependent on assumptions and and personal prejudices and received knowledge; in the hands of a blasé reporter, these attitudes resist all nuance - as brownmane implied - and instead treats its audience with a kind of contempt while curiously assuming we share a smug superiority. I'm thinking not only of the way in which the real-life Enfield Poltergeist story is told to us - kitchen-sink poverty and strife, crafty fraudulence, 'woo', the Grim Seventies, the sly hints of possible immorality etc - but also the manner in which the crimes of, say, the Wests or the Yorkshire Ripper are related to an audience. The grim grubbiness of atmosphere and staging in both the reportage and the fictional treatments is a moral slant, one that has no interest in actually enlightening us.