I’VE arrested a lot of crooks in my time.

As you can imagine, they were a mixed bunch, but – funnily enough – a lot of them had two things in common.

The first was that they were really, really sorry for what they had done. The second (Honestly, Ray, this is the truth) was that it was the first and last time they had done anything like this.

There was a time when I believed them.

But with experience I came to realise what they really meant was that they were sorry they had been caught and while it might have been the first time they had been lifted, it was rarely the first time they had offended.

I was reminded of the old days by the sad, sordid story of Damian McBride, an advisor to Gordon Brown. In the stories I have read he is described as a key Labour insider, a brilliant tactician and astute political animal.

He lost his job after his plan to ginger up the Government’s image was discovered in a leaked email. It was, in essence, to spread a lot of untrue, disgusting personal rumours on the internet about the Conservative leadership; a sort of electronic version of the rude words little boys write on lavatory walls. Apparently, the recipient of his views, another Labour policy wonk, thought his suggestions were “absolutely brilliant”.

Several thoughts ran through my head when I read about this. The first was that it was an April 1 story gone astray. I couldn’t believe that political dialogue had become so debased that someone in a position of power and trust could carry on like this.

The second was how foolish this person had been to commit their appalling comments to email. How many red faces and resignations have leaked emails caused in the past couple of years? Don’t these people read the newspapers?

Finally, I asked myself, how they could misjudge public opinion so badly. As citizens of the real world, we are worried about real issues – jobs, the economy, the environment, crime and where our country is headed. We look to politicians to give us leadership and certainty in these matters. Do they think that with all this on our minds we are interested in tittle-tattle, true or false?

Sadly, the answers to my questions were all positive; yes, political dialogue is debased; yes, they always think they can get away with it; and yes, politicians persistently misjudge the public mood. It’s a bit like Barnum’s maxim about no one going broke underestimating public taste. It is a salutary reminder that we should never give too much credit to the people at the top of organisations, be they ministers, mandarins, bankers or bureaucrats.

They get it wrong a lot of the time.

What we pay these people for is good judgement.

Sadly, in this case you have to question the judgement of the Prime Minister.

Mr Brown has made the obligatory apologies and I am sure he didn’t know what his associate was up to. But he clearly knew what he was capable of and should never have given him a position of responsibility. To use a good old North-East phrase, he shouldn’t have given him houseroom. As it stands, David Cameron must be thinking that to win the next General Election he only has to sit back and watch his opponents implode.

Those crooks I was talking about had something else in common, too. Yes, they were sneaky, cunning maybe; but when it came down to it, they weren’t that bright.

That was why they got caught and why they rarely realised that there was a better, more honest way to lead their lives. Let’s hope our political classes are quicker on the uptake.