POLICE numbers, police powers, and the number of knife crimes are linked, but the causes - like the causes of any other type of violence, lie with disordered families and communities: knife crime is just a symptom.

If the chances of being caught in possession of a knife are high, and the consequences dreadful, then fewer miscreants will risk carrying them - with a consequent reduction in the opportunities to use them.

Taking these in turn:

There has been a reduction in the number of officers available to stop and carry out searches, this is now being addressed with improved funding for recruitment (and, in addition, to more money from central government, our own Hampshire Police and Crime Commissioner has decided to increase his council tax precept to the maximum available) but there is no getting away from it, additional resources will have to be provided.

Even more important however, is that the ability and willingness to carry out searches has been constrained by a policy designed to reduce the perception of racial discrimination. With the increase in stabbings we need urgently to reassess where our priorities lie, and to consider how racial sensitivities can be addressed without sacrificing public safety.

These two address the issue of raising the probability of being caught, but what about the consequences of being caught?

On Monday last week I asked the Home Secretary if sentences were long enough. He replied

“as recently as 2015, changes were made to sentencing for serious violence crimes, including with bladed weapons. While it is right that the courts make decisions on sentencing based on the evidence and the facts in each case, we have seen a rise in custodial sentences. That is important, too, to make sure the right message and right deterrent are set out for these horrible crimes.”

Nevertheless, later in the week there were press reports of a drug dealer convicted of carrying a knife for second time, who received only a suspended sentence.

So, on the following Thursday I challenged another Home Office minister with that information.

She told me “I must, and will, defend the independence of the judiciary, but my colleagues in the Ministry of Justice and I do emphasise the point to the judiciary about the public messaging of sentences. We impose mandatory minimum sentences for those who are found in possession of knives precisely to get the message out there that this is simply not on.”

Well, self-evidently it isn’t working!

The independent judiciary are going to have to raise their game, or their independence will have to be constrained by taking away their discretion.

So much for addressing the symptoms by catching and punishing perpetrators.

What about the causes?

Instruction can be had from the successful experience of Glasgow, which over a decade adopted the approach of treating violence as a disease, treating the causes with initiatives coordinated across the public authorities.

In the last week the finger of blame has also been pointed at school exclusions, because a high proportion of offenders have been expelled. This is a false trail.

Such pupils have a long history of disorder before they are expelled. The issue is one of our failure to properly make arrangements for them after expulsion.

Quite the wrong thing to do, would be to constrain the ability of schools to expel a pupil who endangers the safety of others and disrupts their education.