The Daily Mail recently launched a ferocious - and politically opportunistic - attack on Harriet Harman and Patricia Hewitt over the National Council for Civil Liberty's (NCCL) relationship with the Paedophile Information Exchange (PIE) in the late 1970s.

In fairness to the Mail, its archives show it was always relentlessly opposed to PIE's attempt to use the "sexual revolution" to legitimise its members' predatory and exploitative desires.

At the same time, the NCCL and some other liberal organisations gave PIE too much space to be heard, more from an argument about free speech than sexuality.

Nonetheless it is fair to say the Mail - and the opponents of PIE on the left at the time - was right and the NCCL was wrong.

But a stopped clock is right twice a day. If the Mail wants to look at the history of morality, it needs to look more closely at its own archives.

Many people are aware of the thoroughly reactionary ideas the Mail held for a long time about gay people.

So the Mail reported Labour's 1985 pledge to equalise the age of consent for gay and straight people under the headline "Gay rights fury," giving the first, most prominent quote to a backward delegate ranting about homosexuality being "an illness and a sickness in our society. Because of this unnatural act we have the disease of Aids spreading throughout the world."

This was just one example of the Mail's anti-gay bigotry. But perhaps the most surprising aspect of Mail morality lay in its attitude to teenage girls.

The Mail, rightly, had no problem condemning PIE's interest in sex with children. But it had a more ambiguous approach to court cases where adult men were prosecuted for having sex with teenage girls.

The Mail was in fact as likely to condemn the girls and make apologies for the men. The Mail's misogyny outweighed its concern for protecting the young. The Mail was keener to tell off "bad girls" than care about vulnerable youngsters.

So in 1969 the Mail reported a 19-year-old convicted of unlawful sex and indecent assault with two 13-year-olds under the headline "Tube girls who look for sex."

The Mail highlighted the man's defence that "young girls under 16 travel round the London Underground hoping to pick up men," and uncritically reported his claim that he was trapped because "the girls kept pulling up their skirts and were flirting with him."

These attitudes persisted into the '70s and even the '80s.

In 1975 a 41-year-old man was sent to prison for five years for sex with three 14-year-olds. The Mail's headline for the case was "The lecher and the unpleasant little girls" - he was bad, but so were they.

In 1976 a Mail headline read: "Teenagers tempted 'night of sex' men."

Men in their twenties were found guilty of sex with under-16s, but the Mail began the story with the claim that "two schoolgirls tempted two men into a night of 'debauchery'," giving prominence to the men's defence that "they were very willing girls and very mature."

In 1978 the Mail's headline read: "Trapped by the pocket money sex girls." Four men in their fifties and sixties were found guilty of underage sex.

The Mail called the girls prostitutes. According to the Mail, "the call girls were a gang of schoolgirl friends aged between 12 and 15" who trapped the "dirty old men" by having sex with them for cigarettes and 10 pence pieces.

The Mail was sympathetic about the men's loss of reputation and the judge's claim that "these girls were little more than prostitutes."

They were excited by the judge's claim that "shameless society" was to blame, because "eroticism is regarded as good and pornography is easily obtained."

The Mail's tendency to blame underage girls in sex cases reached a particularly unhinged moment in a piece by its star columnist Lynda Lee-Potter from 1983 headlined "It's the era of the teeny temptress."

Lee-Potter was absolutely against girls being involved in underage sex. But she was also sure who was to blame. Talking about 14-year-olds, Lee-Potter claimed: "They are frequently girls who attract men, not inadvertently with their bodies and baby-doll innocence but with their conscious minds, with practices wiles, with a knowing awareness of their formidable power."

She was convinced "they are no longer victims, they are instigators." She claimed: "The disturbing fact is in the 1980s that it is now the children who are making the running, choosing their conquests, selecting their prey."

I was a teenager in the late 1970s and can remember that morality very different, very odd, and thankfully going through very big changes.

Being gay had only been legal for a decade and gay people still faced police harassment and routine public attacks.

The idea that women could be "asking for it" in sexual assaults was very common. And while the Mail got it right on PIE, it was still mostly wrong on morality and still churned out some very ugly rubbish about young women.