Investigations into historical child grooming cases were significantly delayed because a city council heavily redacted pages of evidence, a report has found.

His Majesty’s Inspectorate of Constabulary and Fire & Rescue Services (HMICFRS) found some material provided by Manchester City Council contained pages with only a few words visible on them.

While the watchdog said this “made it impossible to assess the evidential value of the information”, a new evidence-sharing process had since been agreed.

Manchester City Council said “complex” rules about sharing personal data meant prosecutions could have been jeopardised had some information been included.

The delays came to light as part of an inspection into the historical handling of child sexual exploitation cases by Greater Manchester Police (GMP).

The review found the force had made significant improvements after a series of damning reports into its handling of allegations.

The HMICFRS review was commissioned in 2024 by Greater Manchester mayor Andy Burnham to look at the “current and ongoing provision”.

The report noted that Greater Manchester’s 10 local authorities all had their own agreement about what information would be shared with police.

“Some are willing to share all available information and do so promptly and without redactions,” the review found.

“Others will only do so in accordance with strict rules on what can be included.

“This has led to significant delays in investigations and in the preparation of evidence for court.”

It noted how Operations Green Jacket and Bernese had been “particularly affected by these delays”.

Only one person has been convicted as part of Operation Green Jacket, which was launched six years ago to investigate child sexual exploitation in south Manchester in the early 2000s.

Operation Bernese was set up to investigate child sexual abuse following the death of 15-year-old Victoria Agoglia in 2003.

Victoria, who was in care, died of a drugs overdose two months after reporting she had been raped and injected with heroin by an older man.

“Material provided by Manchester City Council took many months to arrive and was so heavily redacted that some pages contained only a few words,” the report found.

“This made it impossible to assess the evidential value of the information.”

Manchester City Council said it had been “committed from the outset” to bringing offenders to justice.

A spokesman added: “The sharing of personal data is a complex legal area. Failure to follow the relevant guidelines correctly would risk such information being ruled inadmissible in court, serving to jeopardise prosecutions rather than to advance them.

“As this work has progressed, we’ve been able to develop information-sharing protocols with the police which have enhanced processes and been so successful that they have been adopted elsewhere.”

HMICFRS said GMP, the council and Crown Prosecution Service (CPS) had since agreed a new way of working together.

“Investigators can view and assess unredacted documents remotely,” HMICFRS said.

It said while this was “far more efficient and effective”, it had required the process to be restarted.

HMICFRS highlighted how GMP had made significant improvements in how it investigates child grooming cases.

The watchdog found the force had a “strong multi-agency approach to investigating child sexual exploitation” and had “significant resources committed to support these investigations”.

At the time of the inspection, the watchdog found GMP had live investigations into “multi-victim, multi-offender” child sexual exploitation inquiries involving 714 victims and survivors and 1,099 suspects.

However, it has since been clarified that 170 had been arrested and that there are now 269 known suspects.

The number in the published report includes multiple names and descriptions for the same suspects.

GMP now has a specialist Child Sexual Exploitation Major Investigation Team with 98 dedicated staff, working with statutory and non-statutory agencies to support victims.

HMICFRS also noted GMP had a “good strategic and operational leadership and governance arrangements in place for investigations”.

But there were “various training gaps” and previous failings had resulted in an “irrecoverable loss of trust”.

Speaking ahead of the publication of the report, former detective Maggie Oliver, who resigned from GMP over its handling of the Rochdale grooming cases, said: “They have been through the most horrific childhoods that you could imagine.

“They’ve got no reason to trust anybody but when they do put their trust in the system, it’s unforgivable that they are failed again and again and again.”

Michelle Skeer, His Majesty’s Inspector of Constabulary, said: “We found that since 2019, when GMP started to review its non-recent child sexual exploitation investigations, the force has improved its understanding and approach to investigating allegations of child criminal and sexual exploitation.

“It is clear that the force has for many years been trying to provide a better service to those who have or may have experienced sexual exploitation.

“But for some, trust and confidence in the police had been lost, and the force would not be able to rectify their experiences.”

GMP’s Chief Constable Sir Stephen Watson said he wanted to reiterate his “apologies to those whom we have failed in the past”.

“I am sorry that when you needed us, we were not there for you,” he said.

Sir Stephen said he was pleased the report had recognised significant improvements within the force but added there was no room for complacency.

“To those who are responsible for these repugnant crimes – as is now very apparent – we will pursue you relentlessly,” he added.

A second report by Ofsted, which was also commissioned by Mr Burnham, found there was “much good practice”.

Inspection findings show that across Greater Manchester, the response to children who are at risk of exploitation, and those who are being exploited, was mostly good, Ofsted said.

But some local authorities had areas which could be improved, including responses to children who go missing and who are deemed to be at low risk of exploitation and “greater professional curiosity and recognition” of the needs of older children as they transition into adulthood.

Mr Burnham said he was “confident” Greater Manchester’s system was “in a demonstrably different and far stronger place today than it was when the failings happened”.

He said: “The effect of the assurance review I commissioned has been to usher in widespread culture change across all [of the region’s] bodies.

“Never again will any child here be labelled or dismissed when they come forward to report concerns.”

The CPS has been approached for comment.

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