Boris Johnson’s crackdown on crime is a smokescreen – but it will work like a charm on former Tories

It bears all the hallmarks of a Boris Johnson policy. An attention-grabbing announcement that involves great public expenditure on infrastructure and is immediately dismissed as absurd by anyone with any expertise in the subject.

Where once there was the “Boris Island” airport, the garden bridge, the cable car to nowhere, now there are to be 10,000 new prison places, at a cost of £2.5bn, money which Sajid Javid, the chancellor, has already approved.

Being seen to be tough on law and order, principally by locking more people up for longer, is a direct appeal to the type of voter that has abandoned the Conservatives for the Brexit Party, whom they urgently need back.

Announcing the new policy, the prime minister has said we must “reverse the balance of fear”. Currently, he believes, the public is more frightened of criminals than criminals are of the law. There is, naturally, absolutely no evidence whatsoever to indicate that harsher criminal sentences deter criminals, at all. Much of the United States still carries the death penalty. It does not diminish the vast number of people it locks up, nor its stratospherically high murder rate.

Within the announcement, made in an article in The Mail on Sunday, are gentle nods to the “liberal Conservative” prime minister he has claimed he wants to be.

“We cannot allow our prisons to become factories for making bad people worse,” he writes. “We need to reduce overcrowding, beef up security, and do more to educate in jail.”

Countless think tanks and prison reform groups have wasted no time at all in making clear that 10,000 new prison beds will do nothing to address the chronic problems prisons currently face, not least a lack of training and re-education programmes which are already insufficient to serve the overall prison numbers.

Successive Conservative prisons ministers, such as Rory Stewart and more recently, David Gauke, have indicated that the most sensible way to reduce overcrowding, and reduce reoffending, is simply to get rid of prison sentences of six months or shorter, which serve no great purpose other than to dramatically reduce the offender’s job prospects on release, and as such increase the likelihood of reoffence.

Johnson has also pledged to boost police stop and search powers, pre-emptively attacking the “left-wing criminologists [who] will object”.

The left-wing criminologists in question tend to be the ones who trouble themselves with the actual numbers. Figures indicate that the more indiscriminate way in which stop-and-search was done before 2010 simply led to a lower arrest rate than the more targeted system that has been in operation since.

But these are complexities that will not concern the voters who must be won back, close to zero of whom are unlikely ever to have been stopped and searched themselves. The communities whose lives will be made miserable by such things are a lost cause to the Conservatives. As such, and as always, they do not matter.

Usually, Johnson’s smokescreen, expensive and nakedly populist schemes are themselves stopped and searched, for evidence, by experts, and they are then halted before too much damage can be done. The mad airport scheme was ended by the Davies Commission. The garden bridge was also completely dismissed.

Now he is in charge, it may not be so straightforward.