IT is clear now, then, for anyone who failed to cotton on, or still has the sexual mindset of a 1970s celebrity high on fame and testosterone, that the following acts are not OK.

Flicking a 15-year-old girl's nipples and sliding a hand under her skirt; "fumbling" up a 17-year-old's skirt in a public situation where it is hard for her to move away; jiggling a colleague's breasts while she is broadcasting to the nation; pinning a student against the wall of a campervan and forcing a tongue down her throat; stroking a hotel ­receptionist's bottom; groping a colleague's thigh; asking a student nurse if she is wearing stockings then thrusting a hand up her skirt. If you're contemplating doing any of this, stay that urge. Resist the crime - for it is a crime.

Last week saw a jury find Dave Lee Travis found not guilty of 12 counts of indecent assault, and those were some of the acts he had been accused of. He was found not guilty, but his court case triggered another examination of what the sexual culture was in the 1970s - and in looking at it, and hearing a flurry of tales and anecdotes, we found that culture to be guilty.

No-one can any longer pretend that the jury is out on whether any of these acts are actual crimes. We now have it in black and white, in newspapers and broadcast reports, that these acts are criminal - albeit that Dave Lee Travis was not guilty of them.

And this is becoming increasingly clear, as more and more cases come to court: whether it is broadcaster Stuart Hall, who pled guilty to 14 charges of indecent assault, or Coronation Street star Bill Roache, who was found not guilty of historic sex offences. If you're a man, and somehow, up until recently, it had escaped your notice that it's not OK to give a teenage girl a lift in your car then lunge over and stick your tongue down her throat (as one of Stuart Hall's victims has described), you should by now have learned otherwise. If you're a woman and some guy had jiggled your breasts at work, then you will have learned that you don't have to keep quiet about it. Hearing it again and again like this, in historic abuse case after historic abuse case, can't help to send out a strong message.

And that's needed, for there is no doubt that a fair few people did think such behaviour was OK. Recently I talked to sociologist Ellis Cashmore, who has looked into this subject and said he thought that in the 1970s, such behaviour was probably regarded as a perk of the job. "It may disgust and repel us now," he said. "But that's the way it was. Not a violation of a code of ethics, but par for the course, the right of a senior."

So, perhaps we needed to take a long, cold look at the kind of things some men, particularly famous ones, used to think they could do - and then spell out the fact that we now think it was wrong. And the process of bringing to court historic abuse cases has had that profound effect. The message goes out, whether these men are guilty or not, that it's no longer acceptable to grope, jiggle or flick without consent. Doing so is not just a bit of a laugh that you can get away with. It's criminal.

Dave Lee Travis's case is the first to come to court from Operation Yewtree, the Metropolitan Police's investigation into sexual abuse allegations initially triggered by the Jimmy Savile case. Many are saying the operation has failed its first test. But I'd say it's to the Metropolitan Police's credit that it is sending out its own message - almost as potent in this failure of conviction as it might be in the success - that it is taking "sexual abuse very seriously".

As Detective Chief Superintendent Keith Niven put it last week, it is showing that it is intent on ensuring "all victims have a voice". Some may still want to call the operation a "witch-hunt". They may want to portray those accused and found not guilty as victims - and perhaps they are. But the overall process is a good one.

It would be nice to think, as we shake our heads over these accusations, that opportunism is consigned to the past. But it isn't entirely. The kind of abuse of power, position and glamour that, for instance the Hall and Savile cases involved, has not quite been banished. Rather, as Cashmore said to me, it tends to be confined to the most beautiful in society. What's striking about the likes of Jimmy Savile and Stuart Hall is that they were not stupendously handsome. Today's sexual opportunists are more likely to be footballers and rock stars and are "likely", said Cashmore, "to be doing it in more disguised ways".

Of course, these cases don't solve the problem. Issues of consent seem as complicated for the young as ever (it looks like a jungle out there in the world of sexting and revenge porn). But at least we are now defining the very basic rules. The guidebook is being properly and publicly spelled out. And, most important of all, the process is showing that there is room for women's voices. Each case serves as a demonstration of this. And that is the key message we get from this process: from Dave Lee Travis through to Stuart Hall, from the not guilty to the guilty, that women are finally being heard.