The Metropolitan Police’s approach to tackling corruption within its ranks is “not fit for purpose”, a watchdog has found.

Damning findings published today - March 22 - found that the force has not learned lessons from the notorious unsolved murder of private investigator Daniel Morgan.

Mr Morgan died in the car park of the Golden Lion pub in Sydenham, south-east London, in 1987.

The home secretary called in Her Majesty’s Inspectorate of Constabulary and Fire and Rescue Services (HMICFRS) after an independent inquiry into the Met's handling of Mr Morgan’s case found it to be institutionally corrupt, saying it had concealed or denied failings to protect its reputation.

Inspector of Constabulary Matt Parr said that the Met had “sometimes behaved in ways that make it appear arrogant, secretive and lethargic” and that the watchdog’s 20 recommendations for change must be “among the commissioner’s highest priorities” in order to restore public trust in the force.

This report stopped short of calling the force institutionally corrupt, but concluded that the Met's procedures for rooting out corrupt staff are “fundamentally flawed”.

He said: “It is unacceptable that 35 years after Daniel Morgan’s murder, the Metropolitan Police has not done enough to ensure its failings from that investigation cannot be repeated.

“In fact, we found no evidence that someone, somewhere, had adopted the view that this must never happen again. This will be understandably distressing for Mr Morgan’s family and friends, to whom we send our condolences.

“We found substantial weaknesses in the Met’s approach to tackling police corruption.

"From failing to properly supervise police officers who have previously committed offences, to inadequate vetting procedures, and much more besides, it is clear that the current arrangements are not fit for purpose.

“The Met’s apparent tolerance of these shortcomings suggests a degree of indifference to the risk of corruption.”

According to the findings, the Met has recruited people with criminal connections over the last two years, while more than 100 employees have committed offences.

Some of these decisions “may have been justifiable, but the force failed to properly supervise these people to lessen the risks”.

It was also found that property and exhibits procedures were “dire”.

Hundreds of items were not accounted for, including cash and drugs, and in one instance, the security access code for a property store was written on the outside of the door.

Furthermore, the force does not know whether all those in sensitive posts – such as child protection, major crime investigation, and informant handling – have been cleared to the level of security vetting needed.

In addition, more than 2,000 warrant cards issued to personnel who had since left the force were unaccounted for.

It has also emerged that the Met still “does not have the capability to proactively monitor its IT systems, despite repeated warnings from the inspectorate”.

Such monitoring is used by most forces to help identify corrupt staff.

Priti Patel said she was “very disappointed that serious issues still persist”.

“Standards must be immediately improved. I expect the mayor of London and the new commissioner to reverse these deficiencies as a matter of urgency," said the home secretary.

The watchdog did positively acknowledge the force’s ability to "investigate the most serious corruption allegations", an expertise that is relied upon by other forces.

It also praised its confidential reporting line and support provided to whistle blowers, and recognised that the Met had greatly reduced the number of personnel who were not security vetted.

The Met's deputy commissioner Sir Steve House said: “I am professionally disappointed that some of the elements that support the service in countering corruption have not been working well enough. This is already being put right."

He insisted the Met can be the “police service that London deserves”, vowing to continue trying to solve Mr Morgan's killing.

A £50,000 cash reward for information leading to a successful prosecution – one of the largest rewards ever made available by a UK police force – is still being offered.