Children at risk of abuse or neglect face even greater danger because of a new system designed to cut costs and speed up care proceedings, the Government has been warned.

Figures seen by The Times show that since the new system was introduced last September, the number of applications to take children into care in London has dropped by 30 per cent as local authorities struggled to make it work. London was one of a dozen areas – and the biggest – chosen to pilot the new system. The Government was unable to provide data for the other pilot areas.

In some London boroughs applications to courts for “care orders”, which are legally required to take children into local authority care, have fallen by 75 per cent since the pilot began.

Ministers admit that they are aware of the drop in care order applications but say they hope that the reduction is because more children at risk are being cared for by family members – although they concede that they have no evidence of this.

Under the new rules, known as the Public Law Outline, social workers are now required to carry out extensive “preproceedings” work, gathering all the evidence needed for their case, before they apply for a care order.

Lawyers say that social workers are not properly trained to build a legal case without help from the court and fear that the prospect of the extra work without guidance is putting them off pursuing care orders.

Under the old system the case was built up once formal care proceedings were under way and, crucially, under the direction of the judge who would help social workers by telling them exactly what the court needed to see.

John Simmonds, head of policy at the British Association for Adoption and Fostering, said that the drop in care orders was worrying and criticised the decision to “rush out” the new system nationally before the pilots were properly evaluated.

“The Government should be very concerned that a large group of children are at additional risk following this drop-off in the number of proceedings. Such a fundamental change affecting highly vulnerable children being taken into care should have had greater evaluation before it was rolled out. We feel the whole thing has been rushed out,” he said.

“We have not learnt any lessons about what worked well or not so well in different pilots. We have heard anecdotally that in some pilot areas there have not been any care proceedings issued at all since the new system came into force.”

Martha Cover, a senior barrister at Coram Chambers and an expert in care proceedings, called the sharp fall in care orders alarming. “We know that the level of concern is already very high before a local authority takes action, so to see a fall of 30 per cent in applications issued is very alarming. I don’t think it is due to a 30 per cent fall in the level of risk to the children of London,” she said.

The most recent research, conducted by the University of Bristol, found that children have been known to the local authorities for some time in 91 per cent of cases in which care orders are eventually sought, with 42 per cent a result of “unplanned crisis intervention”. Those figures suggest that, even under the old system, social workers waited until the child was under serious threat before taking action.

Ms Cover said she feared that a sharp rise in the court fees to instigate care proceedings, revealed in The Times last week, could be a further deterrent. A spokeswoman for the Ministry of Justice admitted that ministers knew that there had been a drop in care orders in London but said they hoped that it was as a result of more children at risk being placed with other family members, although there was no evidence to back this up.

She said: “We are aware there has been a drop in care proceedings applications in London since the introduction of the Public Law Outline.

“New statutory guidance issued by the Department for Children, Schools and Families requires local authorities to ensure all other safe options, such as wider kinship care, have been explored before issuing an application, and this may well be having an impact on applications.”

She added that it would be some time before an evaluation of the new system had been completed.

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