A landmark judgment has ruled that local authorities can be sued if they fail to protect vulnerable young people and children in their area who are considered to be at risk, regardless of whether they are officially in care.

The Supreme Court has restored the right of children to sue for negligence where a local authority has failed to protect them from harm, overruling a previous Court of Appeal decision which gave social workers exemption from liability in such cases.

Campaigners said the ruling brought a “real sense of justice and vindication” for children at risk of possible sexual, physical or emotional abuse and neglect, who can now bring claims for compensation against local authorities who fail to investigate and take action to protect them.

Peter Garsden, a partner at Simpson Millar, who represented the two children's charities involved in the litigation, said that following the conclusion of the legal action many abuse and negligence cases against local authorities that were put on hold pending a decision would now be able to progress - providing "much comfort" to the victims.

He continued: “This is a groundbreaking decision that has served to clarify the law as far as the duty of care that social workers have towards young people and children who are not necessarily in a care institution, but are known to be at risk.

“This decision affects some of the most vulnerable members of our society and we are delighted that those affected will continue to have access to the justice that they deserve in instances where they are let down by those they have put their faith in.”

The decision follows a UK Supreme Court hearing which took place last July relating to a case in which Poole Borough Council was accused of failing to protect two children in the care of their mother from the antisocial behaviour of neighbours.

Simpson Millar represented Article 39 and The Care Leavers’ Association during the hearing, both of which felt the need to intervene in the case in order to draw attention to the "terrible impact’" abuse can have on children.

Carolyne Willow, director at Article 39, which fights for the rights of children and young people who live in children’s homes, prisons and other institutions, said the charity was "incredibly relieved" by the ruling.

“We are particularly concerned about the continuing scandals of mistreatment in child prisons and local authorities’ failures to take robust, protective action," she added.

David Graham, national Director of The Care Leavers Association, which provides supports care leavers of all ages, said the judgement would give care leavers a “real sense of justice and vindication, as well as financial compensation for harm that should never have happened".

He added: “We hope the courts will now quickly deal with the backlog of cases from adults who were failed as children.”

The Local Government Association (LGA), which represents councils in England and Wales, said: “Looking after and protecting vulnerable children is one of the most important challenges that councils tackle every day, making sure they have the care, support and stability they deserve.