YEARS ago a detailed critique of the Metro­politan Police would have been shocking because the force – though in fact far from perfect – enjoyed a reputation of being effective and mostly incorruptible.

Today, our everyday experiences leave us with no difficulty in believing that corruption and inefficiency exist throughout the ranks. The shock in reading journalist Tom Harper’s Broken Yard, a new critique of 30 years of Met policing, is in realising just how wide­spread and rotten it is.

The acronym ACAB – all coppers are bastards – once a taunt among a small minority, is looking more like a reasonable analysis of how things are.

Well, not all coppers, obviously. Harper’s depressing exposé of the fall of the Met reveals some who do their jobs competently, uphold the law and tear their hair out at the practices of colleagues, watch as their diligence is undermined by the criminality and incompetence of many they work with.

But as he reveals in this thoroughly researched take-down of London policing, the Met have long been in crisis and the nine million Londoners whose safety they are entrusted with are being horrendously short-changed.

And with this week’s news about David Carrick, a serving Met officer who has admitted sexual offences stretching back over a 20-year period, Scotland Yard face yet another crisis.

With morale rock bottom, 12 years of swingeing cuts meaning they simply can’t do the job required – ask anyone who has been the victim of a burglary – the Met, once admired the world over, is shown to be both institutionally rotten from the top down, and lacking the basic tools to solve crimes.

Broken Yard does not suggest things were once all Dixon of Dock Green perfect, although it points out the success of the Labour government’s Safer Neighbourhood policies. Harper explains how corruption in the CID was rife in the 1960s and 1970s – but how officers eventually got a handle on criminals in their ranks.

However, it never really went away: using the murder of Stephen Lawrence and the subsequent hopeless half-hearted investigation as a starting point, Harper takes us through 30 years of scandals that have seen the Met discredited, at war with its Whitehall paymasters (interestingly, the force that is described as once being full of Conservative voters now has a police officer saying none will ever vote Tory again) and not able to do its job.

Harper reveals an institution that is riddled with corruption, racism, sexism, officers scuppering each other’s work as they compete for promotions, and basic incompetence.

At the root of all this are a number of factors. They include criminals working as officers, ranging from the corrupt to the psycho­pathic, to sweeping cuts that make the job virtually impossible, huge rises in “new” cyber crime that require new skills and resources, and the drug laws that give criminals easy access to huge incomes, which in turn fuels other criminal activity.

We know many of these stories already, but having them laid out end to end joins the dots and creates an overall picture of despair.

Tom Harper

The scandal surround­ing the murder of Stephen Lawrence is a relevant starting point. Harper includes links between officers investigating the case and the father of one of the convicted men, how officers spied on Stephen’s parents, and how they bullied and targeted Stephen’s best friend.

This exposé is linked to those that follow by a thread of corruption, incompetence, of internal politics and lack of resources.

The unsolved killing of private investigator Daniel Morgan – another high-profile case – is covered in lurid detail, and leads neatly into Harper’s consideration of the relationship between the police and his former employers, News International. Harper’s explanation of the phone-hacking scandal offers more than the well-worn narrative about sleazy, immoral journalists paying off greedy cops. He charts the failings of the Leveson inquiry, and finds a way to explain the conduct of News of the World reporters. He shows how some reporters were thrown under the bus to save the executives and keep Rupert Murdoch from being too heavily censured.

Former NotW crime reporter Lucy Panton was one such scapegoat. She was made to reveal her sources in the Met as Murdoch tried to shift blame from the managerial strata to the workers in newsrooms. Her testimony does not exonerate her fully but it does show the lengths to which the rich and powerful will go to conceal their behaviour.

It demolishes the few bad apples argument about News International – and, while he is about it, Harper demolishes the same excuses for serial failings of the Met.

In the case of murderer Wayne Couzens, who killed Sarah Everard, Harper highlights how the police referred to their colleague as a “former” officer to deflect blame. This ignored the fact Couzens was a serving officer when he killed Sarah. He also speaks to detectives who are willing to question why Couzens got away with suspect behaviour for so long – and they ask why the investigation into Couzens’ crimes has been shelved now he is behind bars.

One senior officer says the Met should now be reviewing every missing persons case in the UK, and comparing it to Couzens’ movements. Couzens has the hall­marks of a person who has killed before – his pre-planning suggests as much, while his criminal history shows that his behaviour wasn’t a strange aberration. He’d been molesting women for years. Colleagues in the Kent force, where he served before joining the Met, nicknamed him “The Rapist”.

We are reminded of the lies told after the killing of Jean Charles de Menezes. The narrative around his death, hurriedly cooked up by the Met, remains in the public mind.

How many of us recall being told he was carrying a bulky rucksack, that he ran away from police, vaulting a ticket gate, running down escalators, failing to stop when asked to. All lies told by officers as they sought to justify the deadly errors they made.

Boris Johnson’s reckless, illegal parties at Downing Street during the pandemic prompts Harper to wonder how the police, busy nicking people for small infractions of lockdown rules, managed to be in attendance yet not see a thing. The backlash from public opinion was the final nudge needed for the Tories to sack their leader, yet the police’s investigation is shown to be seriously lacking.

Harper’s work is meticu­lous. He has sourced transcripts and police files, court reports and off-the-record briefings. He has spoken with straight and bent coppers and criminals. This means while we have heard the stories before, Harper offers an insiders’ angle, and it is revelatory in its findings.

What are the answers? Harper identifies the problems so those at the top have no excuses. They include the cuts in the number police of officers – 20,000 in 10 years, and hundreds of detective posts currently unfilled.

Former Met Police commander Roy Ramm notes how senior officers are managers who have done little real police work, have never gathered evidence or presented it in a witness box. This dislocation means there is a lack of understanding about how detectives work best.

Until this changes – and until a caveman canteen culture is addressed – the crisis within our police force looks never ending.

• Broken Yard: The Fall of the Metropolitan Police. By Tom Harper. Biteback Publishing, £20