Paul Wilson was jailed for life, in July 2011
A nursery worker who raped a toddler had a "special relationship" with her that Ofsted and a council were aware of but failed to stop, a review has found.
The actions of Paul Wilson, of Birmingham, were allowed to continue because of poor nursery management and failings in inquiries by authorities.
Wilson, then 21, was jailed in July 2011, after raping the girl at Little Stars Nursery in Nechells, Birmingham.
The nature of the relationship should have rung alarm bells, the review said.
Carried out by the city's Safeguarding Children Board, it said there was a failure to properly investigate concerns raised by staff.
As well as the management failings, the serious case review found "interacting factors" on the part of Ofsted and the local authority to investigate properly worries about Wilson's behaviour.
Concerns were also raised about the availability of resources to the police to respond to the general rise in abuse by perpetrators using the internet.
Wilson, of Newbold Croft, Nechells, also groomed 22 other girls and admitted more than 40 offences related to grooming young girls on the internet and distributing indecent images, during the case.
Wilson, who worked at the nursery for 18 months, had filmed himself on his mobile phone raping a toddler there.
Jane Held, Safeguarding Children Board: "Whenever
there's a concern you must talk to the children"
The review found the lack of supervision of him, failure to understand the risks of "special relationships" with individual children, the layout of the nursery and "the weak safeguarding practice" within the nursery" combined to create an environment "where the external factors that might have deterred the perpetrator from abusing the child were missing".
However, responsibility "for this awful abuse must, and does, lie with the perpetrator" who was "clever, duplicitous and manipulative and took advantage of weaknesses in the system", Jane Held, independent chair of the multi-agency board, said.
"In this case there were unfortunately a number of weaknesses in the way that nursery was run and a number of opportunities to intervene earlier and prevent the continuation of abuse which were missed," she added.
The board said the report made eight key recommendations which were being addressed.
Ofsted said it "very much" regretted its inspection regime in 2010 did not help to stop him sooner, but stated it had "long since strengthened" inspection and investigation practices and would "carefully study" the report.
Jail term reduced
Its regional director for West Midlands, Louise Soden, said: "Local authorities have the lead responsibility for investigating child protection matters and we have worked to clarify our respective roles so that nothing falls through the net."
Birmingham City Council said it was "very sorry" it failed to respond to the concerns about Wilson.
A council spokesman said: "[We] fully acknowledge that a referral to us was not followed through, and that this meant that Paul Wilson was able to continue undetected for a longer period.
"As soon as we became aware of the flaw in our process we immediately put measures in place to ensure only qualified social workers take referrals.
"Improving our services to children remains our top priority and we reaffirm that commitment."
West Midlands Police said it acknowledged the findings of the independent report.
Det Ch Insp Garry Billing, of the Public Protection Unit, said: "As a force, we are continuously looking at ways to improve working with our partners, particularly around how we share information to enhance our child protection services.
"The force now has in place a centralised referral unit to ensure a more effective response and consistent approach."
Wilson was jailed after admitting two counts of raping the child at the nursery.
At his original trial, he was ordered to serve a minimum of 15 years in prison. The Court of Appeal cut this to 13-and-a-half years in February 2012.