The government has backed down over plans that would have allowed social services departments to set aside the rights of vulnerable children.
A key part of the Children and Social Work Bill is being axed after Lord Laming, who chaired the Victoria Climbie inquiry, joined a campaign against it.
He met Education Secretary Justine Greening to oppose the changes.
Labour had described the plan as a "dangerous proposal".
The legal duties in question were laid down in several acts of Parliament and related to nearly all the social care services children receive from local authorities
'We have listened'
They cover statutory rights on child protection, family support, rights in children's homes and fostering, support to care leavers and services for disabled children, among other areas.
The idea was that councils could have applied to set aside specific rights in order to try out new ways of working.
And this sparked concerns that child protection services could become open to privatisation.
A spokesman for the Department for Education said: "We have listened to concerns raised about introducing the power to innovate, which would have meant councils could test new approaches in order to support the country's most vulnerable children.
"In recognition of this we are not taking forward that particular aspect of the bill."
An amendment, tabled by Labour and backed by Ms Greening, will be added to the bill in the report stage.
Shadow education secretary Angela Rayner said: "It is an unprecedented climbdown for the secretary of state to sign Labour amendments removing the flagship policy from her own bill just days before the Commons could debate it."
She said Ms Greening had been "reduced to sneaking out this humiliating announcement in the middle of the night in the hope that no-one will notice."
Earlier, amendments made in the Lords, stripping out clauses of the bill related to innovation, were taken out in the Commons.
The change of heart followed a meeting between Ms Greening and Lord Laming, the former Lord Chancellor, Lord MacKay, and the chief social worker, Isabelle Trowler, among others.
About 50 organisations publicly opposed the proposed exemptions - including the British Association of Social Workers, The Care Leavers' Association, Women's Aid, Liberty and the National Association of People Abused in Childhood.
Carolyne Willow, director of Article 39 - a group formed to oppose the bill - said it was an enormous relief that legal protection for vulnerable children and young people would stay intact across the country.
"I hope children and young people get to hear that so many care leavers, parents, carers, social workers, academics, children's homes, parliamentarians, lawyers, paediatricians, charities, trade unions and campaigners fought for their rights for months, and that ministers admitted a mistake and did right by them."