The appearance of Julie Walters on BBC Two in Filth: The Mary Whitehouse Story will remind many of us of the counter-productive influence of that Midlands schoolteacher. Whitehouse reduced to absurdity what should have been a serious debate on the effect of the mass media on moral standards.

Mary Whitehouse launched her Clean Up TV campaign in 1963, blaming a perceived moral decline on the BBC and other leading cultural institutions. She had a genius for choosing the most ridiculous targets, obsessing over the “bloodies” in Till Death Us Do Part, or sounding the alarm at an exposed breast, while failing to see that these were tiny fissures caused by the shifting tectonic plates of the wider society.

Her honourable intentions were soon overwhelmed by the love of self-promotion, and conversations with her turned into a catalogue of the number of times she had been quoted by journalists and asked to appear on TV. Eager for publicity, she agreed to be interviewed by Mrs Merton and the puppets on Spitting Image. But she failed to see that she was embraced by the media because she represented no threat to them - she came across as a batty old lady, out of touch with the modern world, but nonetheless determined to hog the limelight.

She neither commissioned nor deployed research - the ammo necessary to win the debate - because she felt that things should be accepted on her own say-so. When Winston Churchill introduced his Private Member's Bill in 1986 to bring broadcasting authorities within the provisions of the Obscene Publications Act, his supporters were desperate for material on the effect of TV on children. The only help they got was a supply of magazines featuring large photographs of Whitehouse accompanied by tributes from clergymen to her bravery and wisdom.

She liked to claim credit towards the end of her life for making things better than they had been in the 60s, but most parents today would say they are immeasurably worse. The once mighty BBC is now a minnow in an enormous media pond that comprises not only dozens of scarcely regulated TV channels but violent computer games, the internet, rap and hip-hop music and other unhappy influences on young people.

The belief that we should try to protect children from influences that sexualise them prematurely or cauterise their emotional development is not an eccentric one. Unfortunately, because of her, it necessary to prefix expressions of concern by saying: “I don't want to sound like Mary Whitehouse but...”. Not a glorious legacy.

Robert Whelan is deputy director of Civitas and was formerly director of the Family Education Trust

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