In February 1993, Karl Watkins (20) was convicted at Hereford Crown Court in the UK, for making love to pavements.

He made legal history by becoming the world’s first pedophile, a pedestrian who explored new footpaths and then became hopelessly obsessed with having sex with them.

Watkins had been fingered many times as the man found face down on paving stones with his pants around his ankles. One shocked boy described seeing Watkins’s bare bum, moving up and down on the cold, grey and unyielding surface.

PC Trevor Plod told the court that he had been proceeding in a southerly direction along the pavement when he observed Watkins attempting to violate his officially-issued policeman’s boots. On closer examination, he found that Watkins was actually trying to copulate with a slab of unemotional and unwilling concrete that might, in whole if not in part, have been under the age of consent but had no means of objecting to the alleged assault.

(OK, we made up that last bit of evidence, but so do the police when it suits them.)

It was also claimed that Watkins had attempted to mount an underpass – in anyone’s book, that’s a monumental challenge worthy of baffled admiration. Many British motorway underpasses and bridges contain the corpses of countless London underworld figures, so there could have been an element of necrophilia in this particular flight of fantasy.

Yet this was accepted in a court of law as evidence supporting the case that Watkins was a criminal, rather than a total nutter.

But, for the time being, let us not overly concern ourselves with such morbid detail.

Instead of being given 50 quid to practise on a real person or a blow-up doll, and asked to explain his curious sexual technique for the benefit of wider mankind, or even being recognised as a human being in need of serious help, Watkins was traditionally jailed for 18 months.

He was soon back in court, on charges of simulating sex with black plastic dustbin bags in front of teenage schoolgirls.

Watkins confessed to a nine-year fetish with plastic sacks and said that he went out at night to spend time lurking about in heaps of rubbish. He had been found in wheelie bins and in the back of dust-carts. Watkins’ ultimate sexual fantasy was to be in a pneumatic and hydraulically throbbing dust-cart at the climactic moment when the bin bags are terminally crushed.

Just imagine: Watkins’ last words to his flattened, exhausted and violated plastic bag: “Did the tin cans, offal and cardboard move for you, darling?”

You might have thought that the British judicial system would have recognised that Karl was far beyond the help of the UK penal system and perhaps needed some assistance from mental health and safety experts. But their judicial system just kept on sending him back to prison.

The chances are that you won’t believe a word of this story, but rest assured: it happened.

Whoever would have thought there could be an offence of making love to a pavement? If it wasn’t true, it would be madly hilarious.

But in our brave new world, the authorities just make up (or deny) the offences and defences as it suits them.

Such as: “The deceased, whose name is suppressed, waved a knife/hammer/gorilla in a manner that frightened the police officer, whose name is suppressed because he shot and killed the offender while both parties were clearly in a bad mood. We’ll explain this in more detail at the inquest in 2008.”

Or: “The police officer did something involving a baton that genitally-offended the complainant, who was 13 at the time and was not taken seriously for another 30 years”, or the charge is “possession of a paintball landmine with the intent of doing something terroristic that we will clarify in roughly two years’ time, once we have created an offence that fits in with the court’s timeframe”.

Or “keeping a dog that failed to sit still while being shot at by police marksmen.”

In October last year, Robert Stewart was discovered in his room by two cleaners at the Aberley House Hostel in Ayr, south-west Scotland, apparently fornicating with a bicycle.

Last week, Mr Stewart admitted to the hitherto unknown crime of “a sexual breach of the peace” in Ayr Sheriff Court, where depute fiscal Gail Davidson described the scene: “The accused was holding the bike and moving his hips back and forth as if to simulate sex.”

Poor, pathetic Mr Stewart. He clearly presents a dreadful threat to society – and ladies’ bicycle seats in particular. It seems that you can’t do anything in private with a piece of machinery, these days.

Evidently, no matter what the real or imagined “danger to public safety and morals”, the Authorities will always find (or make up) an offence to match.

The outlook is therefore bleak for the Urewera Liberation Front.