"Poor Tulisa. The singer and X Factor judge was recently the subject of a tabloid sting, and was recorded saying that she could provide details of someone who could get some cocaine for the undercover journalist. Cue police raids and her arrest.

But lucky Cara Delevingne! The model was caught by paparazzi cameras as a tiny plastic bag of mysterious white powder fell out of her pocket and was swiftly stood on until she could discreetly pick it up. Cue… nothing, apart from a few murmurs from a retail company with whom she had signed a recent contract, to the effect that well, really, gosh, if anything came of the event, they would, you know, probably have to really, like, come down hard on her, or something.

But nothing happened and so they didn’t. A bit like when the allegations of George Osborne snorting cocaine appeared, or the story about Prince Harry smoking pot and drinking heavily at 16 came out (though to be fair, Prince Charles did make him spend a day visiting people in a rehab centre). The claims of the eyewitness to Harry’s 2012 Las Vegas spree that cocaine was being used by people there also fell on apparently uncaring ears.

Similarly, the few snide remarks (“3x3”) about Kate Winslet’s third pregnancy by a third husband have not gained any of the traction that criticism of the likes of Katie Price and Kerry Katona has over the years. Nor have Katona’s mental health struggles and her diagnosis of bipolar disorder been received with anything like the reverence or sensitivity that greeted those of Stephen Fry.

Why? Because Tulisa (“a chav in a tracksuit” according to fellow X Factor judge Louis Walsh), Katona and Price are common and Osborne, Winslet, Delevingne and Fry are not.

And what does that mean? It means that Winslet, Delevingne and Fry have power. Not power they have wrestled from anyone, but power they were granted – handed freely by society and the numinous workings of social convention – at birth. They have freedom because people trust that nothing that middle class people do can be bad – and if it is bad, then it isn’t meant to be so. There are always extenuating circumstances. They are free to do and say whatever they like, because the default position society takes up in relation to their ilk is one of trust.

For Tulisa and her peers, the opposite is true. Society distrusts them, fears them, dislikes the fact that they have broken out of what is supposed to be a tight, narrow little social space that keeps the rest of us safe from their bound-to-bemalevolent roamings.

Lucy Mangan: "Nothing middle class can be bad"