One day, when everything we know is gone, when the last raven has flown the Tower of London, Celebrity Big Brother is as retro as the Corn Laws, and the sun is merely a digital app that you download into your eyeballs, you can be sure of just one thing.

And that is that, somewhere, a bleary Pete Doherty will be standing in a dock, being told by a judge, in no uncertain terms, that what with this being his eight millionth driving, drugging, breathing offence, that he really is a very naughty boy indeed, and as such is sentenced to go straight to bed without any supper.

That's roughly what happened yet again last week, when Doherty, who had been to court before Christmas on one of his many driving offences, where it was found he happened to have a mere 13 wraps of heroin in his jacket pocket, was summoned back to court to explain exactly why that pesky heroin had been there.

He gave a searing defence that he hadn't intended to bring it all to court; it's just that he was wearing “the wrong coat”, and that, yes, he would happily pay a fine, and the only reason he still hadn't paid two grand for his last fine was ’cos he thought his accountant was going to do it.

Oh, and when asked why he turned up 45 minutes late for the hearing, he said it was because his satnav had taken him “around the houses a bit”.

And so the judge at Gloucester magistrates' court agreed that, if he was in private treatment for drugs, then he may as well carry on without interference, because it was probably working.

The proof of this was, apparently, that he was looking better than the last time she saw him, when “he was sweating quite profusely”. (Probably because he still harboured some ridiculous anxiety that a court appearance for a crime one is guilty of might lead to, you know, yer actual prison sentence kinda thing.)

Now let's imagine a burly black man, who maybe looks like a bit of a bruiser, has fathered a kid or two that he doesn't live with, been implicated in violence, has confessed to crack and heroin addictions and also been arrested for theft, for driving offences, for violence.

Well, call me unimaginative, but I can't quite picture such a man getting let off after impressing the judge with his reduced perspiration levels and his ownership of more than one coat.

But Doherty — a weedy, privately educated white guy in a floppy hat, who got a shoal of A-stars at GCSE and was sent on a trip to Russia by the British Council as a teenager because he was so good at poetry — somehow wriggles free.

Someone who toured with him told me he does take drugs backstage, but he makes himself look even more wasted before he goes on — the messed-up rocker thing being his schtick, his poetic appeal. And it's an appeal that somehow casts a spell on 50-year-old judges as powerfully as on 17-year-old fans.

He's like a fire station with those fake towers that firefighters run up and down to pretend they're putting out fires.

Is Doherty just there for judges to practice on?

Is he a placebo? A freemason? A hypnotist? The man is quite spectacularly prison-proof.

Is there a forcefield around him that makes them go weak at the knees when they see him?

Whether the point of law is to punish or simply to get a criminal off the streets, it just isn't happening with Pete, is it? Why not?

The judge conceded, finally, that his behaviour was “idiotic”. But it's not the defendant who looks like the idiot any more. It's her.