The Tories’ intervention on sentencing for knife crime shows that criminal justice is becoming too politicised

The run-up to a general election is always a dangerous time for the application of common sense in the world of criminal justice. Whether it is gun crime, dangerous dogs, anti-social behaviour or, as now, carrying knives, the instinct of the politician has always been to exploit whatever particular scare happens to be occupying the media and the voting public. New Labour was just as prone to it as the Conservatives are now. It is a moment when we should be grateful for the Liberal Democrats.

For it is that party’s existence in coalition that is slowing yet another political raid into an area best left to the courts and the discretion of judges and juries – a mandatory sentence for a second conviction for carrying a knife. To be sure, it sounds attractive, given recent events. The enthusiasm of the Tories for the cause, and Labour’s sympathetic noises, are not difficult to comprehend. The 200 or so fatal stabbings that are committed in Britain each year is 200 too many, as the average parliamentary candidate on the make might put it. So it is perfectly possible to see why the public want something done about it, and why many in parliament are only too eager to satisfy that urge.

And yet the move is profoundly mistaken, and as we have found to our cost in the past, hasty legislation does not make for sound justice. The important point is that the judiciary can already impose harsh sentences for knife crimes – the sanction of a jail term for possession of a blade is used in just over a quarter of cases. And average sentences for the offence are up. Individual judges are in the best place to consider sentencing, not MPs and peers ruling in advance of cases in circumstances they cannot imagine.

It would be a caricature to say that the politicians are seeking to put the judges out of a job by insisting on more and more control over rights properly reserved to the courtroom – but you do wonder whether the Justice Secretary understands why we employ judges in the first place. Besides, there are not enough places in prisons we have for all those the public would like to lock away; the Tories said in opposition that they would build more capacity, but even the forthcoming “super-prison” will only make up for a proportion of the 16 prisons that have been closed since 2010. As things stand, our prisons are, in effect, full.

And so we find Nick Clegg, Danny Alexander and Simon Hughes quivering – cornered in the alleyway of public opinion by a gang of toughs including, on the Tory side, Nick de Bois, Chris Grayling, Teresa May, Boris Johnson, and Michael Gove – with Ed Miliband hovering. Fully tooled up and united by electoral expedience, they menace their hapless Lib Dem victims until they hand over yet another branch of the criminal justice system to political control.

As if that lot weren’t intimidating enough, the usual suspects from the press are also hanging around, ever-ready to duff up anyone they consider “soft on crime”. Quite a mob, and one that has already seen off one liberal-minded Justice Secretary, Ken Clarke who had the temerity to resist stand up to them. There seems little to stop Mr Clegg and Mr Hughes, and with them the criminal justice system, also being comprehensively mugged.