Not everyone looks back on the period of Conservative Government from 1992 to 1997 as a time of national renaissance.

For one thing the Government was beset by divisions over the issue of our relationship with the European Union. There was a weak Prime Minister undermined by speculation over leadership contests. There was also a lack of an effective majority in the House of Commons to push through Government business. Few of us would wish to revisit such a fraught and unhappy era…

Yet there was a development which took place on May 27th 1993 which proved to be of lasting value. Michael Howard was appointed Home Secretary. He has recounted what happened:

“I was given a briefing by Home Office civil servants. They showed me a graph, which clearly displayed the trend in crime. It vividly demonstrated that crime had increased inexorably, relentlessly and almost without interruption under Administrations of all political complexions for 50 years. They said, ‘This is what’s happened to crime in the past 50 years and what will continue to happen in the next 50 years. The first thing you must recognise, Home Secretary, is that there is nothing you can do about it. Your job is to manage public expectations in the face of the inevitability of rising crime.’ “

But rather than passively accept the advice of his sophisticated and liberally minded officials Howard came up with a bold alternative. “Prison works,” became his catchphrase. When he took over there were 44,256 prisoners. During his tenure there was a “rapid growth of 24,200 driven by a rise in volumes of offenders receiving custodial sentences, as custody rates went up from 16 per cent to 25 per cent.” All very crude and simplistic. Except it did work. Crime fell by 18 per cent when Howard was at the Home Office. There were a million fewer crimes in 1997 than there had been in 1993.

In very general terms the trend has remained favourable. Howard’s Labour successors would do some triangulating third-way tut tutting – but then quietly continued his tough approach. The prisons were not emptied – on the contrary the numbers incarcerated continued to rise. The latest figure is 83,364. When David Cameron was Prime Minister crime fell by 20 per cent.

But recently crime has started to increase. This week the figures from the Office of National Statistics offered grim confirmation of that. It is true that the rise has been significantly worse in London. That is an indictment of the record of the Labour Mayor, Sadiq Khan. On his watch knife crime has risen by 50 per cent. The murder rate in London has become worse than New York. But we also need to face up to the reality that crime has increased outside the Capital.

Various caveats apply. Given that crime has fallen in other countries as well, was Howard just in the right place at the right time? No – but technological advances have certainly helped too. Doesn’t rehabilitation matter as well as just keeping the criminals off the streets? Yes, as Howard is the first to agree. What about the causes of crime? Indeed – reducing the number of children languishing in care, better order in the classroom, an end to building tower blocks. The list goes on.

Then keeping track of the crime trend is a bit tricky. In categories where crime (such as sexual offences) has officially increased some of that may be due to be more thorough methods of recording it. Also not only do we deal with two crime measures – the number of offences logged by the police and the estimate extrapolated from the Crime Survey, based on interviews with 50,000 members of the public –  but over the years there have been changes in the calculations. During the Labour Government recorded crime rose, including violent crime, but the Crime Survey indicated a fall.

In a way, measuring crime according to the total number is a bit silly. Last year I got a pile of letters, perhaps a dozen or more, through the door thanking me for applying for various credit cards – by the next post came another batch of letters logging that these had been detected as fraudulent applications. So I suppose I could say I was the victim of a dozen crimes – but I didn’t lose any money. Given the fraud was detected so quickly the criminals didn’t make any money. Still those crimes were logged – but, of course, others mattered far more.

To take another example the latest crime figures show that there has been a decrease in computer viruses. That is most welcome. But the fear of dopily clicking on something on the keyboard that installs a bug – and then having to pay a technician £50 to come round and debug the computer hardly equates to the ordeal of burglary, robbery, rape or murder.

Anyway let’s accept that, very broadly, for more than a couple of decades the menace of crime has been diminishing. But that it is now getting worse again.

The Mayor of London, the Labour Party, the Police Federation, and others will say that more public spending is the answer. But as noted above crime fell during the Cameron years even though spending fell. Much of the police budget does not go on front line policing. Also at least as important as how many police officers we have is what they do – their priorities, their powers, how they spend their time.

The scaling back of stop and search has been a terrible mistake – for which black teenagers have been the greatest victims.

There certainly should not be a focus on pursuing those whose religious beliefs lead them to denounce homosexuality or transgenderism. This sort of indulgence is an affront to free speech at the best of times. But when real crime is rising then pursuing thought crime is particularly outrageous. So the police in Nottinghamshire will grumble about “a lack of resources” to pursue thieves – but can find the time to go after wolf-whistling scaffolders.

There is a constraint in chasing moped thieves – due to health and safety concerns and the incompetence and politicisation of the Crown Prosecution Service. We used to think that traffic legislation did not need to give specific exemptions to the police who are in pursuit of criminals. It was assumed that the CPS would exercise common sense. Those days are long gone.

We should not be defeatist now, anymore than Michael Howard was in 1993. But do let’s remember what we are in politics for. Just as a Conservative Government should be ensuring wider home ownership and a lower burden of taxation, a falling crime rate should be absolutely key to our mission.